PS Cooler - change or not to change?

[Cdrum]

I've been going through our much loved 2002 GMC Envoy w/120000 miles on it, addressing issues that I can find in advance of my son taking it back to college. The Envoy has lived its entire life in Maryland, and mostly been garaged --- but it is almost 22 years old now and showing some age. My son goes to RIT in Rochester, NY where winters are cold and roads salted. So far here's what I've done:
+ new rear brakes, rotors, calipers
+ new engine mounts
+ replaced cam phasing solenoid
+ repaired rear wiper
+ repaired front wiper motor (was skipping)
+ replaced load leveling sensors and re-leveled
+ rear sway bar end links
+ replaced axle bearings & seals, diff oil, and new diff cover
+ new tires & alignment
+ both front wheel bearings have been replaced in the past 18 months
+ topped up front diff
+ replaced HVAC mode motor (made a puller based on this site - hard part was finding the replacement part)
+ replaced seat motor
+ cleaned the butterfly in the throttle body & replaced the plugs
+ new battery

Planned but not done yet -
- checking through the front brakes (no indication of issues, just want to check them)

The Envoy now drives better than it has in years - the engine mounts were a PITA, but really made a HUGE difference. I'll do the oil of course before I send him back.

I'm currently replacing the coolant and noticed the Power Steering Cooler is pretty rough looking. Any thoughts - should I preemptively replace this? Anything else I should check out?

Thanks All!

 

[Mooseman]

If he's going to NY, yes! I replaced mine with an aluminum Dorman I found at the pick-n-pull for cheap or you can also buy a new one. Another option is to install a transmission cooler plumbed into the PS return line instead of the original one.

Some will say to just bypass the cooler altogether. The fluid can get hot but I ran mine without one for about 2 years. I wound up replacing the pump and the rack due to complications from replacing the lines. The pump got smoking hot when the rack was plugged and the pump was putting out full pressure constantly so it can get hot. I personally feel better having a cooler now.

Also check the lines that go above the strut tower as they ALWAYS rust through inside the rubber isolator. That's the reason I had to replace mine.

 

[Reprise]

The Envoy has lived its entire life in Maryland, and mostly been garaged --- but it is almost 22 years old now and showing some age. My son goes to RIT in Rochester, NY where winters are cold and roads salted.

If you can manage it, do something to keep the expected road salt at bay -- oil spray, rust converter, etc. At that age, if the truck starts getting regularly exposed to corrosives, it'll start going downhill really fast, IMO.

I see that Rochester is right off the south shore of Lake Ontario; if it's in the same situation as, say, Buffalo, a lot of 'lake effect' snow can be expected out there. So, snow / salt on a near daily basis.

Pop off the plastic trim cover in the rear hatch and take a look back there, to see if the bottom of the tailgate is starting to rust -- if it is, a can of Rustoleum converter spray can buy a lot of time in that area (I used it on mine 4-5 years ago with great success). Same for the inner door bottoms, especially where the 'skins' are joined together.

And, yeah, I'd keep the P/S system cool, but any outboard fluid cooler (small trans cooler, etc.) can do the job, if locating a replacement is tough. Give the hoses a look-see at the top where they bolt down to the fender, as was suggested. Losing P/S mid-winter wouldn't be fatal, but it certainly makes steering harder -- whether or not snow is on the ground. I'd imagine this would be doubly true for a less-experienced driver.

If it has 4WD, show him that switching over to it manually when needed is better for the truck than just putting it in 'auto' and waiting for it to slip before it engages. From there, basic maintenance (e.g.; oil changes, yearly oil spray) should get the truck to last him until he gets his degree.

It ain't so much the age... it's the miles. LOTS of life potentially left in that truck, at 120K.

 

[Cdrum]

Thanks much - looks like I can Amazon at least the cooler - the hard lines might be a RockAuto order. I'll admit being intimidated replacing the lines...they look like they snake quite a few places, and there is definitely corrosion where they cross the drivers-side-shock-tower.

@Reprise - I hear you on the rust. In the back when I was doing all of the work on the diff etc, I coated it with rust reformer and then followed up with some underbody coating. Honestly, I wasn't too careful, I just tried to hit everywhere I saw rust starting with the reformer and coated the crap out of it with underbody goop. Spray and pray!

I'll do the same on the front -- however, I've noticed there is some weeping on the driver side axle - presumably the axle seal needs to be replaced. That might have to wait, don't know that I have it in me to tackle right now, my recollection is that is involved. I'll keep checking the diff level.

I replaced the rear hatch about 8 years ago, the original had started to rust where the panels are rolled over. I'll keep an eye on the seams and maybe squirt some rust reformer into the panels.

Huge thanks - really appreciate your advice on keeping the Envoy on the road a bit longer. I'm certainly no mechanic, but I really can't justify paying one to tackle these issues when the repairs would likely exceed the value of the truck. This site has given me confidence to tackle way more than I thought I could reasonably do.

PS - I have to give kudos to PCM of NC. Almost exactly 10 years ago I put on a Kooks header and did a HPT tune from PCM of NC. After swapping out the cam phaser I wanted to reset the the LFTs and reached out to Kelly @ PCM of NC. I pulled a log before and after resetting and the LFTs and he checked everything out for me - says the tune still looks dialed in. A decade later - awesome customer service and support!

 

[pell]

My "new to me" 2007 had a bad P/S cooler. I had paid someone to do this on my 2006, they had the truck for almost one week. Pulled the on out of my 2006 donor took about an hour to replace.

 

[Mooseman]

I was able to replace mine without having to pull the bumper. It was a bit of contorting it but it went in.

The new lines will come with new seals. If you want to avoid what happened to me, pre-punch them and cut off the flaps. When I installed my pressure line, it broke off that flap and it went into the rack, plugging it solid. I was able to snake the new high pressure line from back to front over the shock tower. You'll have to remove the fan and shroud for room to work. Check out this post about it.

 

[Cdrum]

I was able to replace mine without having to pull the bumper. It was a bit of contorting it but it went in.

The new lines will come with new seals. If you want to avoid what happened to me, pre-punch them and cut off the flaps. When I installed my pressure line, it broke off that flap and it went into the rack, plugging it solid. I was able to snake the new high pressure line from back to front over the shock tower. You'll have to remove the fan and shroud for room to work. Check out this post about it.

Thanks @Mooseman - I’ve read your other thread now too. Not entirely clear what you mean by the punch and flap but bet it’ll make more sense when the parts show up. I’ll be tackling next weekend if everything arrives on time. As for PS fluid I have a bit Valvoline maxLife - is that ok to use?

 

[Mooseman]

If you mean this stuff, it should be fine. Might even re-soften the seals to extend its life. Can't hurt. I had tried using Dex VI and ever since my bad luck, I went back to PS fluid. Seems thicker and my pump is quieter.

You'll see the plastic flap between the bumper cover and the frame crossmember, unless it's different on an Envoy. It can be moved down. I should have documented it better.

 

[paul2005tb]

Im about to replace my power steering rack, Im trying to figure out if I can replace all of my lines with a higher quality more durable set of lines that can seamlessly connect to my power steering rack and power steering pump and cooler ?

 

[Mooseman]

Lines are lines IMHO. I bought the cheapest at RA.

 

[Cdrum]

Parts have arrived, and I'm going to dive in this afternoon. @Mooseman, following your other thread and with the parts in hand now, I think I understand what you were saying about the punch & flap - but want to confirm. Here is the part, which I believe is the low-pressure-line returning from the rack to the cooler:


And here is what I think you referred to as the flap:

Presumably, that flap is some sort of check valve. Are you suggesting I just punch/cut that out before installation to avoid it breaking off and jamming the rack?

 

[Mooseman]

Yes. Mine broke off and jammed the rack. I see no purpose of a check valve and would be a bad one at that. Mine with both flaps cut off is working perfectly.

 

[Cdrum]

Update -

All done, but it was fight. Could not have done it without details on here, and a few informative YT videos. Some notes:

- in the replacement lines I purchased, the high pressure line from the PS pump to the rack no-longer uses a cup seal, rather it uses an o-ring. This required removing the pressed in cup seal - I did this by threading a 3/8 bolt into the seal until it lightly bottomed, and then used a crow bar as a drift under the head of the bolt, and a good hammer whack. Popped the old cup seal out. The high pressure line went to the lower-fitting on the rack.

- extracting the new lines and installing the new was a bear. I removed the upper A-arm bolts, and dropped the arm down. This gave plenty of room to extract the old lines and install the new.

- I decided to reuse the low-pressure cup seal on the rack, since it was not leaking. Seems to be holding.

- I attempted to reinstall the rack lines (low + high pressure) from the side behind the front wheel. No good angle to see it or manipulate into place. Instead, I went from the topside down, which required using a 2-step stool and a long stretch past the brake master cylinder. This allowed me to get it aligned and then to pull both lines in with the 8mm bolt.

- Trying to not remove the radiator fan and shroud, I was able to extract the center/lower clip snaking a rather comical chain of extensions some where around 30 inches in length. Really this was easy. HOWEVER, reinstall didn't work out so well - the clip (or at least mine) had to be opened to remove the old lines. I could not get it back tight around both lines and get the bolt lined back up, or re-tightened with extensions. Basically not enough room to put the bolt in from below. I used a bit of 14 gauge copper-wire through the holes to tie it down. I think this clip is pretty important given the close proximity of the fan.

- I removed the front bumper cover to replace the PS cooler - pretty easy.

- I used an oil extractor on the PS Pump return line to "flush" the system when refilling. I was concerned about junk that may have found its ways into the system while reassembling - this worked well and had little bleeding to do. The old PS fluid was well past it.

- about $150 for parts; labor probably clocks in around 7 hours over 3 days, with breaks to apply rust reformer and under body coating. Quite a few moments of WTH (cutting back the inner fender well to clear the A-arm bolts) and maybe a few doubts that I was in over my head!

Next need to tackle the outer front axle seals...hopefully it can make it until Thanksgiving.

 

[Mooseman]

I knew there was a version of the line that uses o-rings instead of the cup seal. I guess it depends on which style you get. Instead of the Sunsongs, I got the FVP that said "OEM design".

Good job 👍

 

[Cdrum]

I knew there was a version of the line that uses o-rings instead of the cup seal. I guess it depends on which style you get. Instead of the Sunsongs, I got the FVP that said "OEM design".

Good job 👍

Gotcha - I was a leery of extracting the cup seals, and more importantly driving the new one in, blind, which is why I just reused the low pressure side's. No drips yet on my cardboard telltale.

Thanks much again for your guidance and help!

 

[paul2005tb]

when my PS cooler failed I sure wish I had replaced it sooner, because you cant really drive it with no oil, it will destroy the pump. The NewEngland salted roads are a nightmare and sometimes I feel paranoid, thinking that they really oversalt the roads up here so that they can put us in a new vehicle sooner ... I decided to install a standard kind of Dorman cooler that is sold for transmissions. I then chose to mount it about 6 inches higher than he OEM cooler location.

 

[Cdrum]

when my PS cooler failed I sure wish I had replaced it sooner, because you cant really drive it with no oil, it will destroy the pump. The NewEngland salted roads are a nightmare and sometimes I feel paranoid, thinking that they really oversalt the roads up here so that they can put us in a new vehicle sooner ... I decided to install a standard kind of Dorman cooler that is sold for transmissions. I then chose to mount it about 6 inches higher than he OEM cooler location.

I have to agree - the PS cooler is a no brainer. I picked one up on Amazon for $70. The hardest part is removing the front bumper cover - which honestly is pretty simple.

Now the PS lines - they are another story. I'm glad I did them and I would do them again, but its not an easy job.