Towing question with 2003 Envoy XL 4.2L I6

[{tpc}]

So I originally started this out on another forum, but apprantly this one is the best to pose my questions and situation to.

Anyways, we have a 2003 Envoy XL with the 3.42 gear ratio, 4.2l l6, 4x4. According to the VIN decode, it says Gross Vehicle Weight/Brake System is 6001-7000/Hydraulic.

The door tag says GVWR = 6400 lb, GAWR FRT = 3200 lb, GAWR RR = 3400 lb and then a few lines down Model T15806 Payload = 1353 lb.

I have also read somewhere that towing cap for this vehicle with the 3.42 gears in 5100 lbs?

Now this is my wifes truck. She bought it new in 2003, said it had the towing package on it, as is evident by the factory hitch.

Why I am asking all this? Well we are looking to purchase a travel trailer, which is stated at 4380 lbs dry weight. Add in a 30 gallons of fresh water, now were at say 4620 lbs. Plus some food and clothing...and other stuff. Website also states hitch weight at 460.

Anyways, I am think we are at close to max, if not a little more. I know we aren't going to break any land speed records, or get very good gas mileage, but that doesn't concern me. I plan on picking up a brake controller and a weight distributing hitch. I'm fairly certain the truck has a trans cooler, but would an additional one be necessary? I also read a thread about adding or replacing some anti-sway bars, which for around $100 didn't seem like a bad idea.

At any rate, is this kind of tow doable, assuming we aren't climbing mountains and what not? Basically we want to be able to pull this thing now in state (michigan), but maybe a few years from now upgrade the truck so we could take a trip out west.

Thoughts? All the numbers are somewhat confusing.

 

[The_Roadie]

Welcome! You should be fine, and people are posting what they tow in a related thread. The stock truck has a small trans cooler built into the bottom of the radiator, but everybody who's towing seriously and cares about transmission longevity seems to throw $50 at a medium size add-on cooler like a Hayden. Plenty of threads here and on trailvoy discussing them. I know I wrote one back there. WD hitch (properly and carefully set up) is essential, and a good brake controller like a Prodigy can also deliver peace of mind.

 

[c good]

Trailblazer Transmission Cooler I6 After looking over all my options, this was a little pricey, but the "Plug and Play" aspect of it helped with my decision. I'm as thrifty/cheap as the next guy but the no cutting into lines, excellent instructions, pretty simple install overall sealed the deal with me. Also, don't tow in "D". Best to stay in "3" and just go easy on it. HTH c good

 

[TB_KSV68]

You should be fine..

The plus side is that you have a "Weenie Dog" and know the history of the vehicle. The ENVOY is well up to your task.

Just make sure all fluids are up to date. That means all fluids !!

Get an Aux. Trans. cooler , WD hitch , and a decent brake controller.

Watch the road well ahead and enjoy your trips until you upgrade.

Lord knows Bill & I have hauled more with less........

 

[{tpc}]

Thanks for the replys, even though I don't know what a weenie dog is, I'm glad that the truck will be up to the task.

Any dangers in having the transmission flushed and fluid replaced? I'll have to talk to her and find out if she has ever had this done, as it probably should be. I have heard before, maybe not with this specific truck though, that doing this can lead to issues with the trans maybe slipping or something? I guess what I am trying to say is I want everything right before we do anything, but I don't want to do something that potentially is going to land me in the repair shop. Any thoughts on that?

We haven't had many issues with the truck, save for the occasional hard start, and the gauges which I have two I need to replace the stepper motors on. Oh and the fan clutch, and water pump. Considering I was able to replace the water pump myself, I find that issue to be minor lol.

 

[The_Roadie]

... I don't know what a weenie dog is,...

Wiener dog is our good-natured term for an EXT/XL long wheelbase truck. They even race!

View attachment 32275

 

[6716]

Also, don't tow in "D". Best to stay in "3" and just go easy on it. HTH c good

To add a dumb question ... why tow in 3 rather than D?

 

[C-ya]

To add a dumb question ... why tow in 3 rather than D?

So the transmission doesn't have to lock and unlock the torque converter (and still downshift) as needed for hills. This adds heat into the tranny. Back in the day, GM used to have "Tow/Haul" button on the shifter to keep the TC from hunting like that.

 

[glfredrick]

It would be better if you had the 3.73 gears but shifting into 3 will help on hills.

I towed a 2-axle car hauler w/off-road vehicle behind mine. Towed just fine and ran with the big dogs most of the time. Even blew a trailer tire once and had no problems handling it to a stop. Never had any issues with "driving" or "handling" while towing. Solid platform with good handling and did just as well as the Burban behind me.

Long-term towing effects required the replacement of the rear axle bearings, but that is a job many TB platforms require anyway with time and miles. Definitely needs a transmission cooler... I over heated mine several times in the hills of southern Kentucky. I ended up swapping in a newer transmission, but that was not purely due to towing, rather rusted out lines caused a total melt-down. Make sure the trailer brakes are working. TB will stop the load, but tons better with good trailer brakes.

Largest load I hauled was a Jeep J20 truck that had a bed full of steel scrap. Probably over 10K on that load! That was noticable...

View attachment 32288

 

[DocBrown]

I'll offer a slightly different spin on this. Really just so you know what you are getting in to. I have essentially the same Trailvoy, same basic specs and tow a 4700# trailer. I will say this, you're smart for not using this combo to tow in mountains.

First off, ignore the "dry weight". For towing purposes that is a fictional number. No trailer truley weighs its dry weight when you are towing it. Dry weight is an estimate based on the materials and components used to build it. It does not include options like A/C, awning, spare tire (some don't come with a spare), TV, etc. Most trailers made in the past few years have a yellow sticker on the side of the trailer with the "weight as shipped". That's a better number and fairly accurate, but better yet, you need to know what the GVWR of the trailer is. That's the max weight it can be before its considered overloaded. So the real cargo capacity of the trailer is the GVWR minus the "weight as shipped".

For example my trailer's dry weight is 3,660. Sound like an easy tow, right? IIRC, the shipped weight is just over 4000#. So there are 340# of options installed. The GVWR is 4750#. That leaves me with about 700# of cargo capacity. We have about 350# of "stuff" (I know because I weighed it). Not including food. It doesn't take much. Now we're pushing the total cargo capacity of the trailer.

The towing capacity for a 4wd ext/xl with 4.2 and 3:42 gears is 4900#, not 5100#. That includes a full tank of gas and the driver. The more important number to know is the GCVRW. That's the max total weight that both the truck and trailer can be together. I think ours is 10,500# (should be on the door sticker). Assume that your trailer will be up to capacity, that is the GVWR, in my case 4750#. If the GVWR of the TB is 6400# and the cargo capacity is 1353#, then the weight of the truck unloaded is 5047#. Add 5047# to 4750# and you get 9797#. In theory that leaves 700# of unused capacity. Doesn't quite work that way. The appearance of available cargo capacity is decreased by the tongue weight of the trailer, which in my case is easily over 600#.

So you can see that I am right at capacity with my trailer. Your trailer's dry weight is 4380#, 720# more than mine. The real shipped weight is probably more like 4700#. Add your stuff and the weigh of any passengers and you will almost certainty be over your rated capacity.

I used to tow a 3500# GVWR trailer. The TB towed it beautifully. I took it out west in the mountains and it was a pleasure. Not so much with my current trailer. Adequate is the word I would use with my current setup. Where I used to get 11/12 mpg in WI with the smaller trailer, I now get 8-10 mpg. That's at 60 mph. It also needs to shift into second and run at 4000 rpm or higher far more often. Keep in mind this is not like towing a boat, pop-up camper, or car. Its a box that has the worst drag coefficient possible. Hold up a sheet of 4x4 plywood and run into the wind. You get the idea. Very hard on the truck. So it works, its stable and safe, but certainly not ideal. Like you I'm planing on only towing in WI for a couple of years but eventually I'll get a 1/2 ton quad cab with a V8. Or maybe even another Trailvoy with a 5.3 and the 3:73 or 4:11 gears.

Regarding an axillary trans cooler, I never had one with the old trailer. The truck had 150k on it when I bought the new trailer last year. I did put one on for the new trailer and extra 1k lbs though. Change fluids regularly, and make sure to use Dex VI. Its known for running cooler than the factory Dex III that these came with. I put in a shift kit last summer and my trans is in amazingly good condition. No visible signs of wear on the separator plate and no damage to the actuator pistons. Though I did change the separator place and actuator pistons as part of the upgrade.

Just for point of reference, the tongue weight rating of 460# is dead weight. With a w/d hitch that number increases to something like 780#. The 900# number on the hithc is just for the hitch itself. If the W/D hitch is properly setup your tongue weight will be 12-15 % of the trailer weight.

Sorry for the info overload, but I think its important stuff!

 

[sLAsh]

I have to agree with doc. I tow a 12 ft popup with a trunk along with a couple canoe s and I would have to say the envoy is adequate at best for that. I would not want to haul much more than that.

 

[TollKeeper]

With the 3.42 gears, it will only just be adequate. I have the same gears on my Envoy, tow a 1000lb trailer, and 1000lb worth of toys. Going up the grades to Winter Park, or Eisenhower... Its like watching hair grow. It gets there, but you will hardly, if ever, reach speed limit. And that's with a 2000lb trailer, and maybe 100lb of gear. No where near its GVCWR. Next time round, I will get 3.73, or more gears in the tranny (like the new 8 speed ecodiesel from dodge).

 

[C-ya]

Wiener dog is our good-natured term for an EXT/XL long wheelbase truck. They even race!

View attachment 19549

You know what's funny - I don't see my weenie dog as being as long as the others I see while driving around.

Nah, can't be that long...

Sheesh, that thing is a land yacht!




Nope, not mine! :wootwoot:

 

[triz]

With the 3.42 gears, it will only just be adequate. I have the same gears on my Envoy, tow a 1000lb trailer, and 1000lb worth of toys. Going up the grades to Winter Park, or Eisenhower... Its like watching hair grow. It gets there, but you will hardly, if ever, reach speed limit. And that's with a 2000lb trailer, and maybe 100lb of gear. No where near its GVCWR. Next time round, I will get 3.73, or more gears in the tranny (like the new 8 speed ecodiesel from dodge).

Really I've towed much more than that and the truck is very responsive. No issues keeping up with traffic.

 

[DocBrown]

I have to agree with doc. I tow a 12 ft popup with a trunk along with a couple canoe s and I would have to say the envoy is adequate at best for that. I would not want to haul much more than that.

You misunderstood my post. It should be far more than adequate to tow a pop-up. My previous trailer was a 3500# hybrid trailer. A box with no wind resitance. No trouble towing, more than adequate, it towed that trailer beautifully. Its my 4750# trailer that the TB tows only adequately. I towed a 2500# pop-up with a 2000 Pontiac Montana mini-van and it was towed like it was made to tow that pop-up.

With the 3.42 gears, it will only just be adequate. I have the same gears on my Envoy, tow a 1000lb trailer, and 1000lb worth of toys. Going up the grades to Winter Park, or Eisenhower... Its like watching hair grow. It gets there, but you will hardly, if ever, reach speed limit. And that's with a 2000lb trailer, and maybe 100lb of gear. No where near its GVCWR. Next time round, I will get 3.73, or more gears in the tranny (like the new 8 speed ecodiesel from dodge).

Really I've towed much more than that and the truck is very responsive. No issues keeping up with traffic.

I was thinking the same thing. On both of the quoted posts I have to wonder since they are having so much trouble towing relatively small weight with very little wind drag, these guys may have a clogged CAT. Mine clogged a few years ago and holy buckets it could barely get up to speed on a flat surface let alone up an incline.

 

[Mark20]

I concur towing a popup with a TranSport minivan. The combination was perfect. The Envoy also handled the popup perfectly. Moving up another 1000 pounds and throwing aerodynamics out the window was less than pleasing.

 

[{tpc}]

Thanks for all the posts and the help, everyone! We are taking things slow on this one, because first, there isn't any point to buying a trailer if we can't haul it, and second, with all the snow and cold weather, I wouldn't want to deal with it now anyways. The only good thing about this snow and weather is it is allowing me time to get all the stuff we will need without having to get it all at once, and also allowing me to go through the truck a little bit at a time and clear up the things that just need clearing up. I'm sure plugs, o2 sensors, tb cleaning, fluid changes, trans cooler, etc will all be done prior and soon. Even if it won't work, its still stuff that the truck needs.

Also, a friend of mine here at work said before he bought his trailer, the place allowed him to hook it up to make sure he could tow it, so I plan on asking about that as well. If it doesn't work, then it doesn't work. Our goal is really just to be able to tow it around here on the flat lands, until we can get a more suitable vehicle.

If it doesn't work out, maybe I'll just have to get some snowmobiles or jet skis to tow around! But I really appreciate the discussion on this.

 

[TollKeeper]

Really I've towed much more than that and the truck is very responsive. No issues keeping up with traffic.

Being in Florida, that means you have about 25% more power than I do, due to altitude.

With my smaller 250lb trailer, and my 2 ATV's, about 1000lbs, it does wonderfully, and no drop in fuel mileage.

 

[triz]

Being in Florida, that means you have about 25% more power than I do, due to altitude.

With my smaller 250lb trailer, and my 2 ATV's, about 1000lbs, it does wonderfully, and no drop in fuel mileage.

This truck is from the North my friend. Most of my towing has been done up and down the East Coast (NY). It has also made the trip to Colorado Springs with no noticeable loss in power.

Winter is Coming.

 

[TollKeeper]

Colorado Springs is about 6000 feet lower in altitude then where I was having power issues. I was talking Berthod Pass, 11306 feet, Loveland pass, 11991 feet, and Vail pass at 10662 feet. There is about a 20-25% loss in power at those elevations. The truck has no problems pulling those passes with my small trailer, at 1/2 the weight, or with no trailer.

Once I am back in Denver, it pulls just fine.

 

[{tpc}]

As far as brake controllers go, would a tekonsha P3 work for me? Trying to hash out a deal on one right now, but I'm new to all this so no clue as to if it would work, and the website for it leaves a bit to be desired.

 

[The_Roadie]

P3 is a wonderful unit. The web site I looked at is totally complete to make the decision. Overfeatured actually, but that's not a bad thing. Many of us use Prodigys. Fall back to a Prodigy if it saves you $$.

 

[C-ya]

I use a regular Prodigy in my truck and it works fine. The vendor/website I bought mine from has both the Prodigy and Prodigy P2 for the same price. The difference between the two is that the P2 can be mounted at any angle (through 360°) whilst the Prodigy only has a 70° ROM (that's range of mounting!). The website starts with an e and ends with trailer if you catch my drift.

 

[Mark20]

Any Prodigy brake controller

 

[{tpc}]

Should be picking it up monday night! Guy says has everything in the package you would get if new.

 

[Alansd]

My new to me 2003 TB has a tow hitch and plug, but I will have to wire the Prodigy. If it is not a factory tow package are the wires still bundled under the kick panel?

 

[{tpc}]

My new to me 2003 TB has a tow hitch and plug, but I will have to wire the Prodigy. If it is not a factory tow package are the wires still bundled under the kick panel?

Alan, it is my understanding that the wire harness would only be under the kick panel if it WAS a factory tow package. If it is aftermarket, it is still possible that they are there, but I would think they would have to be wired in.

How many pins are in the aftermarket unit may lead to an answer though. The factory one has 7 pins I believe, some aftermarket setups are only 4 or 5, because they are for smaller trailers without electronic brakes (at least from what I found on the internets).

 

[Alansd]

found the harness, installed my Prodigy brake controller. No hassel other than I blew a fuse messing around in there.
Got the conversion plug for the trailer connector too. All is well.

Now I need a trans cooler and maybe airbags.

 

[Alansd]

went out to hook up and do a test run with my Airstream trailer. The hitch on the truck was too high for the ball th get under the trailer coupler. Looks like I will need a drop reciever hitch to get it right. It's always something!!

The photo makes it look even higher than it was...

 

[DocBrown]

Now I need a trans cooler and maybe airbags.

If your weight distribution is properly set up you should not need air bags.

 

[The_Roadie]

Make sure those drop hitches are rated for WD use. The one I got had an extremely heavy duty solid adjustable drop shank with adjustable trunnion. Not a tubular item.

 

[Alansd]

yeah, I am getting a whole new WD hitch with adjustable shank.. Reese has the pro series for only 250 on sale..


By the way my TB has Bilstein shocks in the rear,,, are those after market? I would assume they are.

 

[Playsinsnow]

By the way my TB has Bilstein shocks in the rear,,, are those after market? I would assume they are.

What color is the shock body? Black Bilsteins were OEM. The blue/yellow HD's is what you want

 

[Alansd]

If your weight distribution is properly set up you should not need air bags.

How critical is getting a trans cooler. Before the warmer weather ok? I have a 300 mile trip in late March. Really don't want to spend any extra money right now...

 

[The_Roadie]

Many people tow carefully without an aux cooler. There is a small one built into the radiator. GM would not have rated it with a decent tow rating if that cooler did nothing.

That said, if you have an Android phone with the Torque app and a Bluetooth dongle, you can see what the transmission temp sensor is reading, and have data to make an informed decision with. In the absense of tall Western mountains, you might be just fine towing in 3rd.

 

[Alansd]

My Bilsteins are Blue..

As for the Torque app, thanks for that info. I put the dongle into the onboard OBDII access point?

It would be great to monitor tran temps

 

[Playsinsnow]

My Bilsteins are Blue..

As for the Torque app, thanks for that info. I put the dongle into the onboard OBDII access point?

It would be great to monitor tran temps

Yes, plugs right in. You can leave it in too.
Add the preset GM PIDs and you are good to go. Takes a little navigating the app at first for personal setups.

 

[Alansd]

set up my new Pro series weight distiribution hitch and took my Airstream for the first tow with the TB. It surprised me how well it pulled, and handled. No highways yet, but around the town it was smooth. Brakes on the trailer worked well too. I just have to adjust the head on the hitch a little.

 

[{tpc}]

Alan, what's the weight on the airstream your pulling, just for reference?

 

[Alansd]

Alan, what's the weight on the airstream your pulling, just for reference?

Airstream says it to be 4200 lbs with 400lb tongue weight. I suspect it is a bit heavier. But it is all original inside. Just updated. Its a 1966 model.