04 TB temperature needle drifts to the right when going up a hill

gica

Original poster
Member
Dec 25, 2012
135
Cali
So I replaced the electric fan last year together with the thermostat and temp sensor right next to it. I did this after coming back from Laughlin pulling a boat and it caused it to worm up with the air on going uphill. Had to turn it on heater to go up those hills. Well now I want to go back without the boat and noticed the temp goes to 230 on AC measured on OBD2 when going up the short hill in the city. At night temps are steady at 199-203, during the day with AC no hill 210-215. I pressure washed the ac condenser, I checked the fan parked with ac on and it spins pretty strong wasn't able to stop it wearing gloves and pushing on the side. It does get weaker with AC off. What should I do?
 

Blckshdw

Moderator
Nov 20, 2011
10,665
Tampa Bay Area, FL
I replaced the electric fan last year

Just to clarify, did you mean you replaced the fan clutch? Or you removed the OEM fan, and installed an e-fan in its place?
 

gica

Original poster
Member
Dec 25, 2012
135
Cali
SO usually it was during the day 100 degrees outside. The water pump thermostat and temp sensor are all less than a year old also the fan clutch is the same, all ACDelco except the fan. Last year I pulled a boat to Laughlin and it went to 3/4 had to turn air off and heater on on those hills but it was 110 degrees outside. When I got back I replaced all the above.
So today went the same route that takes me through the cyn and it has a little uphill temp went up to 227 with or without the air on. On the freeway it also went up to 216 and at the light off the freeway went down to 209. The clutch does engage with air on and disengages after 1-2 minutes with it off. I don't know it it's only 2 speeds on the fan or whatever the normal is, I know disengaged you can stop it with a rag and engaged not that easy. Coming back at dask temp at 89 degrees the car ran at 199-203 the whole time with or without the air on. It actually went to 207 at the light.
I ordered another fan and will put it on tomorrow to at least try something.
It's weird cause the ac sometimes turns on by itself and have to press OFF to shut it down.
Cat converter 2 years old, car is not driven that much, maybe 3k miles on it since all have been changed.

Just to clarify, did you mean you replaced the fan clutch? Or you removed the OEM fan, and installed an e-fan in its place?
Yes I removed the oem and installed a replacement from Amazon, which worked ok. Water pump was also replaced ACDelco with thermostat and temp sensor. Cat converter replaced 4k miles ago after market. Old one was completely plugged up. I have evap P0440 code that's been there for years, replaced everything related to it all the way to the tank and the metal filler gas tube that you use to fill at the pump. But I heard it might have a leak right at the tank where the metal tube goes in. there is a fix that cost 150 dollars haven't done it yet.
 

mrrsm

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Oct 22, 2015
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Some Suggestions:

(1) Remove the Transmission Pan, then R&R the Filter and Fluid...and while doing so ... Isolate your Transmission Cooler Lines and Flush & REVERSE Flush the Transmission Cooler...but NOT backwards through the 4L60E.

Dirty Transmission Fluid clogged inside of each Turnaround "elbow" of the 4L60E Fluid Cooler Coils with BUILT-UP Clutch Plates and Steels Debris reduces the chance for a decent Thermal Transfer of Heat leading FROM the Transmission Innards and the Torque Converter towards the Front of the Vehicle where the Moving Air Column can then Carry Off that Excess Heat.


(2) If you can afford one... Borrow or get you hands on one of THESE with a reliable Owner's Reputation for Accuracy and then Check your Transmission Cooler, Radiator, Condenser Coils and Power Steering Cooler for signs of any Recombinant Thermal Overload when all of these awful High Heat signatures from a Running SUV are present:

INFRAREDTEMPGUN.jpg


(3) Consider returning to a Stock OEM Fan set up.

THIS Video will be helpful concerning The Best Way to Flush the Transmission Cooler Radiator Coils and Lines leading to and from the Transmission:


This is a Popular Alternative TC Flushing Method (Courtesy @MAY03LT) ... But with All Due RESPECT... It Does NOT Qualify as a True Flush-Reverse Flush Method meant to DRIVE THE DIRT CLOGS OUT OF THE TRANS-COOLER AND LINES USING A TRUE SOLVENT... FOLLOWED BY APPLYING DIRECT AIR PRESSURE TO CLEAR THE SOLVENT FROM THE LINES:

 
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Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
It is normal, to a point, for temps to climb a bit while towing uphill in hot weather and A/C on. The fan will increase engagement incrementally as the temps rise. Your fan clutch seems to be working correctly as you describe it. 230f i would not be worried about. If you don't have one already, install an aux tranny cooler, which will extend its life as well as reduce the heat transferred to the coolant via the radiator tranny cooler.

A tranny fluid flush is a good idea only if it's due for one. Won't affect temps that much though.

You are towing in 3rd gear right? O/D while towing is a no-no, causing excessive wear and heat.

If after all this you are still worried, you can add a bypass switch to the fan clutch to make it engage 100%. Find the fan relay module in the fuse block and add a switched 12v+ to the leg that supplies the white wire on the fan harness. It will make your truck sound like a dump truck but will give you that extra cooling boost when you need it. Or you can also tap into that white wire.
 

Sparky

Member
Dec 4, 2011
12,927
I would not think the trans cooler has anything to do with the engine temp. Possible partial blockage in the radiator could cause warmer temps, though 230 climbing a hill loaded down does not sound terrible. Maybe go ahead and flush the radiator just to be sure that it is clean unless you did that already.
 

gica

Original poster
Member
Dec 25, 2012
135
Cali
I just changed the fan clutch again and took it on interstate 5 going toward Magic Mountai there are a few hills nothing major and it went up to 126 with or without the ac on. Turned to 90 degrees to engage heater and it just stayed at 123 but not lower. Last year with load in 115 when I turned on the heater the temps I believe were doing this cannot remember if temps were going lower but straight line needle was in the middle with ac on, didn't have the scanner with me. So straight line it goes to 112 driving really nice, get out of the freeway it goes up a little to 116 at the light otherwise 112, and parked at idle it doesn't go up it actually goes to 108 after about 3 min with or without ac.
I know the radiator is fairly new but when installing the different fans some of the metal vanes got pushed together by the fan clutch so that might limit the flow. I hope there is no tiny leak in head gasket. I was wondering if adding a supply fan on the ac radiator to push more air would do anything? Or maybe install it right before the main fan to provide some more f, I read somewhere that a guy installed it and it worked it has to be a thinner fan for the space between the radiator and the main fan.
Also how about the thermal non electric fan, but you have to use software to turn off the pcm checking for signal that triggers the cel.
 
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gica

Original poster
Member
Dec 25, 2012
135
Cali
I already added the tranny aux radiator and flushed the tranny with all new fluid even replaced the pan with one that has a drain bolt.
Everything else has also been replaced. AC Delco 190 thermostat, AC Delco water pump, radiator is 2 years old. Fan Clutch is also new off the market. New CTS also. I tested the wires from the PCM to the relay 45 and fan harness and they show continuity. Using a OBD2 Autel I can read fan speed and it goes to 800 on the freeway. The fan seems to engage but when it goes hotter it doesn't seem to go faster. Truth be told I didn't check fan speed at higher temps. It gets up to 128 or 130 on a relatively short hill on the 405 at Sunset. I tested compression and it's at 205 on all. I used a vacuum gauge and it stays in the green. I tested the exhaust and the gauge showed 0 so no restriction from the cat. I flushed the radiator and filled it to specs.
The only thing I can think of is the speed of the fan. The 45 and 46 relays are side by side and one night the lights went out while on the freeway, and I know it's from the relay. I used the fog lights to the destination which was 2 minutes away and after shutting the car off and back on it was ok. I have a tendency to switch those 2 relays around so maybe that's why I sometimes get hot and sometimes not. On the relay number 4 contact that goes to the white wire on the fan harness shows ground only. I actually took out the relay and jumped 2 and 4 and the clutch got louder but not airplane loud.
on the tester.
Any advice would be appreciated.
 
Last edited:

TJBaker57

Member
Aug 16, 2015
2,897
Colorado
Have you checked the connections from the connector on the radiator shroud to the electro-viscous clutch itself? I had a bad connection at the clutch connector. Pull out the harness connector at the shroud and connect an ohmmeter to the white and black wires. There should be some small resistance like 10 or 12 ohms if memory serves. When I reached around the front of the clutch and wiggled my wiring the resistance jumped all over. The bad connection I had resulted in intermittent fan operation.

This is the connector where I had the bad connection of the white wire.

IMG_20190829_105159.jpg
 
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Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
Which brand fan clutch did you use? Dorman is notorious for failures as well as no name brands from eBay and parts stores.
 

budwich

Member
Jun 16, 2013
2,027
kanata
you did a "jump test" but you used your ears instead of some equipment to measure the fan speed during the test. Do the test again and get out your scanner and see what the fan speed is. This is the maximum speed that the fan will turn at because your "jumper" is providing "full power".
 

gica

Original poster
Member
Dec 25, 2012
135
Cali
It went to only 800 or so Fan Speed which is low I did have the Autel opened at the fan readings. So jumping 2 and 4 did not provide the full blast airplane noise. Maybe the harness is not making full contact or the fan is bad. I didn't check resistance as [U]TJBaker57[/U] mentioned between the black and white wires
This is the fan and I did not wiggle the harness at the fan.
I already contacted the seller to try and get a refund.
Would this be a better choice even though it has some bad reviews?
 
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budwich

Member
Jun 16, 2013
2,027
kanata
It went to only 800 or so Fan Speed which is low I did have the Autel opened at the fan readings. So jumping 2 and 4 did not provide the full blast airplane noise. Maybe the harness is not making full contact or the fan is bad. I didn't check resistance as [U]TJBaker57[/U] mentioned between the black and white wires
This is the fan and I did not wiggle the harness at the fan.
I already contacted the seller to try and get a refund.
Would this be a better choice even though it has some bad reviews?
but what was the engine rpm at the time you did the "jumper test"?
 

Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
That ACDelco is pretty spendy. The Hayden has been our go-to but then the reviews have been so-so.


The Hella-Behr is the supplier to ACDelco. A little more than the Hayden but a lot less than ACDelco.


Test the fan according to this thread. Jumping the relay should lock it up and you will hear it even at idle. Revving the engine will make it sound like a jet engine.

How to test the electro-viscous fan clutch
 
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TJBaker57

Member
Aug 16, 2015
2,897
Colorado
On the relay number 4 contact that goes to the white wire on the fan harness shows ground only

I'm not sure what this sentence means. This white wire should show about 10 or 12 ohms resistance to ground. It will be reading the coil resistance of the solenoid inside the electric fan clutch. If it is much greater or open you likely have a bad connection or a bad fan clutch. Bad connections could be at the fan shroud connector, the fan clutch connector right at the clutch or the ground connector from the clutch to ground "G103" on the radiator support
 

gica

Original poster
Member
Dec 25, 2012
135
Cali
I think I was referring to relay 45 and the white wire contact at the relay which is the middle of the 3 prongs at #4. #5 is from PCM and #2 is from the fuse. When I check with test light I get + on 2 and 5 but negative on 4. So my question is for the fan to engage doesn't the relay have to have positive to the white wire? Just like when I jump it 2 to 4. By the way when I jumped I didn't press the gas to rev the engine. I did it at idle. So I just did the test again by jumping #2 and #4 with the clip and the fan speed went from 480 to 780 and when pressing gas I get airplane sound and fan goes to 2000+ or - so it engages when jumped. I shut down the engine and put the replay back and it takes 2 minutes but goes back down to 480 fan speed and no more airplane sound. I triggered a code also probably the high fan one.
So now what?
How can I get the car to heat up to lets say 230 degrees or 3/4 on the gauge at idle to simulate it for the fan to engage to see if it kicks up the revolutions?
 

TJBaker57

Member
Aug 16, 2015
2,897
Colorado
The rpms you saw with your latest test seem about correct to me. The 2 minutes to slow back down is also in line with what I have read in some posts quoting "official" test procedures and also in my own tests as well.

From post #13 "It went to only 800 or so Fan Speed which is low"

That is not low at all for an engine at idle. With a Tech2 or the torque app we can see the speed requested by the PCM.
 

budwich

Member
Jun 16, 2013
2,027
kanata
As you can see from your "test", you are able to make the clutch basically "lock" to the rpm of the engine. (ie. the "maximum" speed achievable). That's good, that implies that the clutch appears to be working correctly.

As for your "light testing".... "lights" don't tell the whole electrical story. All the light on the white was telling you was that there was a low resistance path to ground.... which is true... its the "solenoid / valve" in the clutch assembly.

It is difficult to know the "duty cycle" of the "clutch fan relay" without a "full scanner" (or torque as mentioned) or scope to look at the waveform.

I am not sure that your system is actually not functioning correctly. In hot weather with A/C on, I would expect a range somewhere in the range of 205-215 at normal speeds.

Having said that, you also need to have "normal engine operation".... have you looked at other things associated with the engine... that might indicate maybe a lean condition resulting in running hotter maybe. Its also possible that your thermostat (even if "new") may not be opening up fully (my guess).
 
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gica

Original poster
Member
Dec 25, 2012
135
Cali
I just drove it right now at 88 degrees outside temp it started out at fully warmed up on the streets 198 to 201 the 201 was at a light then I got on the freeway and went down to 195 and ranged between that and 198. As soon as I hit a small hill of lets say 1/4 mile length maybe less it went to 207 and back down to 198 after. I also sometimes pull a small boat been doing it for years but only 4 to 5 times a year. The boat pulling doesn't significantly change the numbers until I took it up the mile long hill on the 405 north when it went to 230 and I had to turn the heater on. That was late afternoon coming back in the morning going to the launch site it went up to 212 on the opposite side hill. So it's weird.
I do have a P0442 small Evap leak. The fuel trims ST(short) ranges from -4 to -12 and the LT(long trim) stays mostly lower at -5 or so. I don't think it's a big deal. I am trying to purchase a clone Tech2 VXDIAG VCX NANO with Wi-Fi for $100 and download the tech2win on an XP laptop or a win7x32 laptop. I will probably download GDS2 also. Have all the instructions. That way I can test the Evap purges. It would cost on the same neighborhood if I go to shop. I am also looking for a cheap smoke Evap machine in the $60 range to see where the small leak is. I replaced all the valves the purge in the front and the vent in the back, also the pressure sensor in the tank which didn't show much pressure before. I used to have the P0440 code and now I got the P0442 one instead. Even though the Evap showed successful. I see pressure building on the Autel at 3.something then goes back down to -.30 or sometimes 0 at idle. So I think the tank might be leaking a bit at the filler hose to the tank connector which as I read is somewhat expected. But only with a smoke machine and blocking the hose at the vent can I see where it leaks.
So now what. should I change the thermostat. Do they have any that open up at 160s the one I have is a 195 or so from AC Delco. Also my radiator is 2 years old got on Amazon forgot the make I have to go back and look. Could that be also a factor, I saw an AC Delco for around 130.
 

budwich

Member
Jun 16, 2013
2,027
kanata
what gear are you running in when pulling a trailer? The numbers for your trims seem not quite right.... its running rich which means, depending on how long its been running like that, that you may have "chunged your cat".... not good.
 

gica

Original poster
Member
Dec 25, 2012
135
Cali
I am running in 3rd uphill. The cat is about 3 years old but with very little mileage since. I just tested the pressure at the upstream injector and it's 0.
I don't know specifics for Trailblazer but I thought the trim should be plus or minus 5% or at the most plus or minus 10%. What else should I look at in live data. I think I can record it but not sure. The Autel I am using can see evap readings, misfire readings, engine 1,2 and 3 and another one. I didn't se a Lambda reading but other than that it has most of them. If there is some info on the numbers I should look for it would help.
 

budwich

Member
Jun 16, 2013
2,027
kanata
look at your downstream o2 sensor response. As for your trims. If you look at your numbers, you are running as much as -15% (sum). I am just putting out suggestions. As I suggested by others, you didn't indicate what your fan speed was during the aftermentioned "test". As for parts, I wouldn't do anything else yet. I think people have indicated that your response might be somewhat normal.

I pull heavy at 4600lbs with total running near 9600lbs. In 90plus degree weather, I see engine temps running 220 area at times up minor grades or otherwise. It is discerning but somewhat expected. Having said that , I never see trims at the level, that you show. Most in the 0 to 3 LTFT with the STFT waggling around 0, +-5/6. You have checked your back pressure so that's good.

Further, you may try running without a thermostat ..... not sure if it is possible due to the make up of the cooling system (I know my year has an "integrated" thermostat / hose pipe). That will tell your "best" method of cooling that your truck can achieve, in terms of fluid.
 

Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
It's recommended while pulling a heavy trailer to not use O/D at all, leaving it in 3rd. This will lower your trans temps and prevent the hunting between 4th and 3rd which also causes heat.
 

gica

Original poster
Member
Dec 25, 2012
135
Cali
Thanks guys, the STFT runs up and down between 0 to +- 5 when RPM is constant . Sometimes it goes +- 8 and the most I've seen it was -12 but really brief. LTFT never got there. Last code I had was P0442 small leak. I just got the clone Tech2 VXDIAG tool will put it together with a PC to test the damn air system. The EVAP monitor is still incomplete gas between 1/4 and 3/4 and 150 miles later didn't purge. That can cause it to run Lean but to heat up uphill to 230 on some occasions?! There used to be a P0440 but after changing the tank pressure sensor it went to the 442. I will probably get a cheap smoke evap tester at $68 on eBay to do it right.
The car runs great changed headlights to really nice ones with some LED stuff and installed a 7" Android that I connect to my hotspot and get anything you get at home. The android also has the Torque Pro App installed and I get live readings of the engine. For a 2004 it's been brought to today's standard. So these little issues usually are the worst I'd rather rebuild a damn engine than diagnose a air leak.
 

gica

Original poster
Member
Dec 25, 2012
135
Cali
I do believe that the whole ordeal started when I went to Tahoe a few years back and on the way back the cat got plugged up, so I drove back to Los Angeles at 30mph and no power. I think that I put some pressure on the system. After that I replaced the cat with an off the market one for 375 installed. But the P0422 started right after and I haven't done anything to fix it. I assume that's what caused the cat to plug up so bad. As I stated in the thread I did replace everything after that the radiator though from Amazon, water pump, thermostat, temp sensor and gas cap all AC Delco. Lower main hose is also new. Fuel filter new. The fan clutch I replaced twice and no difference for the overheating but from tests the fan goes to 100% when jumped at relay 45(#2 to #4). I did not check the resistance anymore don't remember if I did it last year. I am hoping the plugged cat didn't cause the head gasket to develop a pin size leak. I remember doing compression test last year and all was good. I hope after P0422 goes away something changes.
will report sooner this time. Any other advice will also be appreciated, thanks in advance.20200708_231706.jpg20200708_231654.jpg20200708_231644.jpg20200708_231717.jpg20200708_231644.jpg
Cannot believe how good the shape of the tank lock ring on the pump is. Looks brand new even though it's original.
 
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Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
Just to get us back on track on this...

Been reading a few threads about this and 230f seems to be the norm while towing with these trucks. In this one, he was able to lower the temp by turning down the A/C blower.

 

gica

Original poster
Member
Dec 25, 2012
135
Cali
Is this the thermal fan you were talking about. În the comment section one mentions a tune. What is this about and how good is it?Screenshot_20200711-030728_Amazon Shopping.jpg
 

Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
So TorquePro is the best app for android car monitoring?
I only had the free Lite.
Does it show fuel level also?

Yes on all counts.

Is this the thermal fan you were talking about. În the comment section one mentions a tune. What is this about and how good is it?

Yes, this would work instead of the original electro-viscous fan. You would need to get the PCM tuned to get rid of the CEL codes.
 

Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON

gica

Original poster
Member
Dec 25, 2012
135
Cali
Yeah I did the tests with the AC and the fan does go faster . I did use a rag at normal temps it is not as willing to spin right(takes an extra 2 seconds or so) away but with the AC it takes it right away to higher speed.
I forgot to mention I installed a transmission cooler on this baby already.
I am gonna go and measure the temp on it using Torque Pro and also see if it shows the fuel level.
So for that do I need to access the Settings option for GM/Opel etc. or is it already there standard.
Is Water Wetter really effective for this issue?
 

gica

Original poster
Member
Dec 25, 2012
135
Cali
So I finally got the app to see the bluetooth adapter and these are the displays I got. I couldn't find on for fuel level. Found fuel remaining.Screenshot_20200711-152010_Torque.jpg
 

budwich

Member
Jun 16, 2013
2,027
kanata
the bad news is that it appears to show the same "bad reading" as your gage (ie. full as opposed to X amount full - 7 gal). It is likely you have a connection problem and unless you can get access to the connector, at least partially dropping the tank is probably your only way forward.

Having said that, you can check some of this electrical characteristics at the PCM connector to determine which wire is having the problem... you might get lucky and just find that a ground is "bad".
 
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Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
Is Water Wetter really effective for this issue?

It might help. I know it does for my snowmobile. Can't hurt.

Your fan clutch also seems to be working so I wouldn't bother to change it. Have you tried to spray the A/C condenser and radiator with a hose? Dirt and bugs can impede flow.
 

gica

Original poster
Member
Dec 25, 2012
135
Cali
Here's the fan test. Temps went to 228F at idle with AC on. It was 100plus today, It took awhile but it got there. Then I did the test as shown in the Dropbox video.


As for the sending unit for the fuel gauge issue I ordered another one same brand and will see what happens. I want to know more about the tuning deal. Found a website where they talk about it. Haven't found the actual soft that I need to do it, turn of the option


 

gica

Original poster
Member
Dec 25, 2012
135
Cali
I am also reading this thread about MPG. Mine is really bad at around 14+ which is not so good. So I read about the manifold cracks, and since mine had a completely plugged catalytic converter a few years back( I mean 100% looked like it melted itself) and I drove all the way from Tahoe to Los Angeles at 35MPH towing a boat and 4 occupants in the car, took 14 hours to the Grape Vine and towed from there. I mean that was the last time my car didn't heat up. After that I changed the cat, most cooling system parts, plugs, tranny flush and added cooler, even put a different tranny pan with a bolt release for oil change. So crack in the manifold? Don't hear it so don't know they say read the short and Long Trims. Here's the thread:

 

budwich

Member
Jun 16, 2013
2,027
kanata
Here's the fan test. Temps went to 228F at idle with AC on. It was 100plus today, It took awhile but it got there. Then I did the test as shown in the Dropbox video.


As for the sending unit for the fuel gauge issue I ordered another one same brand and will see what happens. I want to know more about the tuning deal. Found a website where they talk about it. Haven't found the actual soft that I need to do it, turn of the option


so you are saying that you were able to stop your fan with the temp at 228? Seems strange.

you can readily check your fuel trims with most live data interfaces. That may help in your investigation.
 

Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
At that temperature, I would think it would be fairly difficult to stop it but it does seem to be engaged somewhat.

As a test, when it's at that temperature, put +12v to the relay leg that supplies to the white wire of the fan connector. This will put the fan to 100% engagement. If your temperature drops, then I would suspect that your fan clutch is not engaging enough for what it is being commanded.

I have towed my #5300 trailer with the TB 4.2L and although she was huffing, it never got to that high a temp on my current EV fan. Neither has my Saab with the 5.3L and the thermal clutch with the same trailer.

I may have missed it but have you replaced the coolant temp sensor? ACDelco?
 

gica

Original poster
Member
Dec 25, 2012
135
Cali
So to check the trims should it be at idle or at a certain RPM?
Yes the coolant temp sensor was replaced twice with AC Delco. That is a good idea with the jumper from 2 to 4 on relay 45.
At 228 it was a bit difficult to stop that fan but it did stop. You guys watched the video right? It could be that the after market cheaper fans don't engage as well as the ACDelco ones.
You never mentioned on the tune for the thermal fan. Is the guy on the forum the only way to do it or can I do it myself.
 

Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
Unless you have tuning software and setup, no. You'd have to send it in. @limequat here or at his site, you can arrange for a tune. He also has loaners if you can't have the truck down for a week or so (may be longer with COVID mail slowness).

Have you thought of the radiator possibly being blocked internally? It can happen, especially if it was filled at some point with the wrong coolant (Dexcool and others don't play nice together) or if bad/well water was used with the coolant (should use distilled water or pre-mixed coolant). A radiator shop could rot it out
 

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