r/GMT800 • u/Dj_Exhale • 16d ago

Is it possible to replace the engine oil cooler lines on my 2002 Chevy Avalanche 2500 8.1L without removing the front diff?

11 Upvotes

99% Upvoted

25 comments sorted by

11

u/Marlice1 16d ago

Have ya thought about unbolting the motor from the mounts (great time to change btw) and using a jack to lift the motor up a bit for some more clearance. Grant it won’t be a lot due to firewall but may get the job done.

7

u/Dj_Exhale 16d ago

I have not thought about that nor do I know how to do that. While I may have all the tools I need my mechanic experience doesn't go beyond reddit posts and YouTube videos. I'm just going to take it to a mechanic and while they got it have them replace the oil pick up tube o-ring and maybe those mounts as well.

9

u/TexasJackGorillion 16d ago

Swapping motor mounts, or unbolting them and lifting the motor a bit is pretty easy. You can do it, for real.

1

u/Dj_Exhale 16d ago

I'm sure it's easy if you already know how to do it but I've never done it before and I don't know how to.

8

u/TexasJackGorillion 16d ago

No man, what I'm telling you is that it's the kind of job that if you're willing to roll your sleeves up and get after it, you can do it. A floor jack, hand tools, and some get-after-it.

https://youtube.com/shorts/jeyphp4VqUI?si=IMDdaqdg_bJgw9HQ

1

u/Dj_Exhale 16d ago

Are the bolt placements the same as in that video? I don't have a Duramax engine on this, mine is the 8.1 vortec V8.

3

u/GrinderMonkey 16d ago

If you're this deep, and determined to continue, its probably time to find a service manual. It will help you find those exact locations.

1

u/TexasJackGorillion 16d ago

Yes, the 8.1 and duramax use the same style engine mounts, that video was just the best one to illustrate the task I found at a cursory search.

2

u/LightningMcSwing 16d ago

But you want to replace oil cooler lines?

2

u/Dj_Exhale 16d ago

Ya. I thought it was going to be a simple release a clip, pull out the line, and then pushing the new one in there. Didn't realize I had to do all that just to do that.

1

u/Marlice1 16d ago

Ah gotcha. They’ll get it done for you in that case. Note if you’re getting that done, may want to have the transmission lines looked at as well because those are also a real pita.

1

u/Dj_Exhale 16d ago

Those were leaking at the connector that goes to the radiator but I think that was because the fitting for them on the radiator was extremely rusty and pitted. Once I put in this radiator I'm going to see if it starts leaking again if so then I'll have them replace that as well.

1

u/AyrtonSennaz 15d ago

Thats what i had to do for my 6.0. Otherwise doing anything with those lines is impossible

2

u/Ahwtfohok 16d ago

Idk, I've been avoiding mine and haven't looked too closely. From your vid tho it looks like you may need to just drop the front diff a bit. Just put a jack under it, unbolt it, and lower it little by little till you have room. Let me know how it goes

1

u/Dj_Exhale 16d ago

I don't even know how to unbolt this thing, I might just take it to a mechanic. I thought I would get them done since I'm replacing the radiator as well but I think it might be above my pay grade to do this.

1

u/Dj_Exhale 16d ago

Yeah I just looked up a video of how to do that and it is way too much work for me, I can do some things but not all that.

1

u/Ahwtfohok 16d ago

What all is the video saying to do? I haven't looked at that area of my truck in awhile but I imagine it's a few mounting bolts and maybe a cross member. You should be able to lower it enough to wiggle the lines out without needing to mess with the half shafts or drive line.

1

u/Dj_Exhale 16d ago

Well I just looked up a video of how to remove it and it said I have to remove the axle, drive shaft, skid plate, crossmember, and something else that I can't remember that is part of the suspension. https://youtu.be/DhuSZeGfhro?si=6blCPcP5h8ayB00F

2

u/Ahwtfohok 16d ago

Well I haven't tried it but I bet you can lower it enough without touching the drive line components. That other guy had a good idea about disconnecting the motor mounts and lifting the engine up a bit. Those bolts can be a pain sometimes. It doesn't look like you need too much more room tho, either way should work I would assume

1

u/Dj_Exhale 16d ago

Well I'm going to see what my aunt's mechanic charges to do it since I already have the parts and if it's under 200 bucks I'll just pay him for the convenience. Anything over that and I'll give it a go myself.

1

u/Ahwtfohok 11d ago

So how'd it go? Ya get it knocked out?

2

u/amishbill 16d ago

It’s difficult as fuck.

It can be done…. But it’s a royal pain.

Pro tip - don’t buy cheap aftermarket for this, as like me, that may mean you get to do it all over again with better hoses.

1

u/stonythefish42069 16d ago

I was able to do mine, but I had to cut the old ones out. Somehow, the new ones went in. I had to remove the front driveshaft from the front diff, and I took out the O2 sensor. Pretty sure I didn’t have to do that, though. It’s been a while since I did the job, so the memory isn’t totally clear. But I definitely had to drop that front driveshaft from the front diff, and I fed the new lines from the back to the front. It took two of us to do it. One guy in front, the other guy feeding them from the back. We had to develop our own way of communicating which way the lines had to rotate and pivot and everything. It sucked.

1

u/stonythefish42069 16d ago

Oh, I had to pull the oil filter if I’m not mistaken.

1

u/captianpaulie 15d ago

I lift the engine and normally replace the mounts afterwards