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2500 Engine Oil Cooler Hoses

Durwin

Charter Member
Full Member
Joined
Apr 8, 2002
Messages
1,352
Location
Sacramento, California
Good Evening,
Have any 2500 owners had to replace the oil cooler hoses? I have about 215k on mine. I replaced them several years ago. Today, they are starting to leak again.
Does anyone know of a better design than the GM parts?
Durwin
 
Just as a heads up. There are really two manufacturers for these hoses that I have found... Dorman and GM.
I have heard complaints concerning the Dorman products. They do not always fit as the GM ones do.

The GM part numbers are:  15065206 and 15753773

I don't know if 1500 owners have these hoses.
Durwin
 
Have you ever replaced one before.
 
One of mine is leaking too. I have new ones but have not changed them yet, but helped a friend change his on his Sierra.. My trans lines leaked the same way at the hose ends where it goes into the fitting. The trans lines are real tuff to change because of the exhaust blocks access to the fittings on the trans but engine oil cooler lines are fairly easy to get to just a little tight where the line supports or clamp the hold the lines under the motor.

Start with line on the motor, remove the wire clips that hold the line into the fitting, wiggle it back and forth pulling it straight out. Have a rag or container ready as the oil will flow when you pull the second one. Let the oil drain for awhile before you pull them at the radiator so you get as much as possible from the cooler. Put in the new ones and your done.

I was going to take my old lines and replace the rubber hose with braided steel lines and AN fittings. And then if it ever starts leaking again change the out or if I'm bored one day...

Randy
 
Had to replace mine about 6 months ago. Not exactly the easiest thing I have ever done. I used the dealer lines. Hopefully won't have to replace them again.
 
I've done this twice... once on my old Av and then on the one I have now.  No, not a fun process at all.  The one I have now has a three inch body lift on it, so it was a little easier getting in the engine bay.  I believe I bought the Dorman hoses this time.  They've been on about a year so far and I have noticed any leaking from them.  Hope this helps.


**** I just noticed that I stated
They've been on about a year so far and I have noticed any leaking from them.
  That was supposed to say I haven't noticed any leaking from them.  Sorry
 
I am suddenly leaking oil near the filter. Is that where the lines leak ?
 
Not usually, they are hard lines at the rear where they go into the block. Unless the o-ring on the tube/fitting failed, but that would be unusual.

One of mine leaked at the crimp fitting where it connects the the rubber flex hose.
 
I need to get it up and see better. My oil filter is wet and the first time it happened was last month we had -20 morning and it leaked on start-up. I changed the filter and pulled my camper to Florida and back  a few weeks later. Noticed a small spot leaving Florida and 16 hours of driving later oil level was full. Got home and parked it 2 weeks ago and moved it yesterday to see a huge spot. I figure if it was rear main seal it would have leaked when driving. Maybe the seal on the adapter is flaky and the heat swells it while driving?  Or maybe the line is leaking at the crimp and the oil is running back along the metal part?
 
Yes look at the lines toward the front, maybe it's leaking and running back. Or because of the extreme cold the oil filter seal passed let some oil by..
 
I agree with Randy when I have my oil filter changed in winter when it warms up the filter is loose to the point I can spin it by hand. They recommend to hand tighten it but I learned to make sure it's tight. Your engine block is cast iron the filter is aluminum they expand and contract at different rates.
 
Yes. I understand  about the filter and extreme cold weather. When it first happened I was sure that's all it was. I changed the oil and filter when it was no longer cold. Didn't drive it at all in between, I was just moving the truck on that cold day when it happened. But now it's warm and a new filter is on so I don't think its the filter. I may not get to look at better this weekend but I'm not going to drive it anyway until I can.
 
Another thing you may want to look at is the valve cover gasket.
 
I did look quick around up top  but will look beter.  I'm still playing lumber Jack before the woods are over grown. My firewood has to get done. I don't have any camping trips planned until July so I have time.
 
Funny you mentioned lumberjacks, did that yesterday but it's too wet today.
 
Rains almost here too. I'm done for the day. Maybe later I will look at the AV. Even though I'm not in a rush I hate not knowing what it is..
 
So today my lumberjack operation had a string of setbacks. The last one being the hitch ripping off my Polaris Sportsman. So, I decided to look at the Avalanche. As soon as I started it I seen oil dripping down so I quicky drove it up some ramps with a tarp under them. Took a look and seen where the oil cooler lines go vertical into the block. Both the lines and fitting are bone dry. As is the hole in the bottom of the inspection cover. The only place I see oil is on the filter and oil pan behind the filter but nothing higher than the filter. Got my wife to start it up while I was under there and quickly seen oil coming from where the filter meets the block. Wtf? It's not 20 below and I changed that original filter with another Mobil one filter before I left. I only hand tighten and never had a problem before now 2 in a row? I guess I'm happy it not the lines with only a little over 35k on her but this filter deal is weird. Maybe I will try a AC Delco filter.
 
I kind of thought that is where it was coming from, that's why I quit hand tightening them and give to a quarter more turn.

Frankly I was surprised they don't unscrew and fall off, but I notice the oil on the ground before that happens
 
There was a bulletin way back about the 8.1L oil filters coming lose after and oil change and the recommendation was to go to 3/4- 1 full turn if I remember right.

I use the K&N and it requires 1 - 1/4 turns, says right on it.. I like them because they a have a 1 inch nut on the bottom and I use a 6 point socket and long 1/2 inch extension to R & R. Makes for easy oil changes.. Just make sure you use a 6 point socket, a 12 point will not grip and good and slip..

I think the PN for K&N for the 8.1L is HP 1011.. I use the longer HP 3002 because I have a lift which allows you to use the tall filter.. You get a full 7 quart fill..
 

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Yeah I think it maybe because of the tiny stock filter, when I start it when it's super cold during winter the oil pressure stays near 80 PSI. I'm thinking of doing that remote filter with the heavy bypass valve you had posted about Randy.
 
I picked up a Baldwin filter. Install it tonight and for the first time in my life will use a filter wrench to install an oil filter  (y)
 
??? filter to install an oil filter
 
OK yeah ya gotta crank that baby down or else it will leak sooner or later. When I take mine to the oil change place they hand tighten it, in winter of course. It's too cold for old guys to be laying on the back on cold ground.
 
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