New to me 2011 Yukon XL Denali

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Very nice find.

 

[donjetman]

131k miles when I proactively replaced mine 3.5 yrs and 44k miles ago.

 

[Geotrash]

How many miles did your truck have on it when you replaced the TC?

About 114,000

 

[jdwood1111]

So I drove the truck again since I haven't in a while and got under it. There is a slight leak still coming from somewhere at the joint between trans and motor as before but when I pop the cover off the bell housing it seems dry inside (hopefully not rear main) and I do not see oil coming down from somewhere up top. If I had to guess I would think its the oil pan gasket at this point but again, it is very mild right now. In wanting to tighten up the bolts slightly, I was unable to get to the bolt shown the picture below due to a black piece of plastic bolted to the block. Does anyone know what this is? Can I remove the bolt on the right side holding it to the block, move it away to then torque the circled oil pan bolt down a little?

 

[Geotrash]

So I drove the truck again since I haven't in a while and got under it. There is a slight leak still coming from somewhere at the joint between trans and motor as before but when I pop the cover off the bell housing it seems dry inside (hopefully not rear main) and I do not see oil coming down from somewhere up top. If I had to guess I would think its the oil pan gasket at this point but again, it is very mild right now. In wanting to tighten up the bolts slightly, I was unable to get to the bolt shown the picture below due to a black piece of plastic bolted to the block. Does anyone know what this is? Can I remove the bolt on the right side holding it to the block, move it away to then torque the circled oil pan bolt down a little?

Yes and yes, or try a 12-pt socket as it should be thinner wall and will fit in there - at least mine does. Also that's not much of an oil leak but I would bet that it's coming from either the o-ring on the plug at the bottom left of your circled area, or the gasket for the aluminum part where the oil cooler lines come out against the engine block. Both are common leak points.

 

[jdwood1111]

Yes and yes, or try a 12-pt socket as it should be thinner wall and will fit in there - at least mine does. Also that's not much of an oil leak but I would bet that it's coming from either the o-ring on the plug at the bottom left of your circled area, or the gasket for the aluminum part where the oil cooler lines come out against the engine block. Both are common leak points.

Thanks! That’s what I thought. I did try a 12 point and still wouldn’t fit. The picture was after I had always wiped the oil off so I’ll take a picture of the leak next time I run it and get under there but it wasn’t that bad. The oil cooler lines were just replaced so I don’t think it’s coming from there but what is the o-ring you mentioned? What is that going to? It really just seems to be wet around the lower half of the engine to trans joint and maybe slightly higher on the driver side. Maybe the oil pressure sensor gasket.

 

[jdwood1111]

So I finally had time to do the front and rear diffs and transfer case! Transfer case seemed quite red still and may have been done more recently than I thought. Gives me high hopes for the transmission. Front and rear diff seemed like they were original as they were black sludge.





Used all ac AC delco fluids and didn’t really run into any snags which was nice! Everything seems good and just waiting for my wife to get back from using the truck and make sure nothing is leaking. Only thing I forgot to do cause I was in a hurry was I put the rear pan gasket on completely dry so I hope that’s ok. I meant to lube it a bit so I hope it doesn’t leak but the gasket was in good shape.

I also removed that plastic plate mentioned previously and snugged down the two rear oil pan gasket bolts too while I was under there.

Overall pretty happy with how clean the truck was under there. Not much rust which is great!

 

[jdwood1111]

Wife got back the other day and no leaks and then I drove the truck around a lot yesterday and did not notice anything leaking upon inspection after! I do still get a small amount of residual at the same rear engine-to-trans so I guess I will try and inspect the oil pressure sending unit with a mirror per some research and maybe the valve cover gaskets as I do not know what else it could be. I will definitely let it ride. Now I just need to figure out the trans if I am going to to myself or have some one do it. I may just wait til the fall when its a bit cooler and tackle it myself with a buddy and save the money. Oh and I will need front brake pads soon otherwise hope everything stays good.

Also, not sure I noticed if it was doing this before I slightly tightened the oil pan bolts but the oil pressure once hot will stay a hair above 20 PSI at idle and then shoots up to around 37-38 on throttle and a little more above 40 PSI when I really get on it. Its around 50-60PSI on cold start up. Everything I have read seems to indicate this is normal but just figured I would verify these pressures.

Lastly, with the range device I am only seeing 12.5-14 MPG riding around town with very little highway. Before Range I was seeing 14.5-15.5 MPG so definitely a small reduction there. I read some people get an improvement but I am certainly not seeing that with my current round town driving. Going to try and save for a blackbear tune but that may be a while away unfortunately!

 

[jdwood1111]

Afternoon All!

So I was reading another post where some one stated they ran the Range AFM Disabler and then once they took it out their lifter got stuck. Is this something to be concerned about at all? Would it be good practice to take out the Range device every once and a while to allow the AFM to engage to keep things lubricated (forgive my exact understanding of how the internals work)? I have only had it in and driven the truck for a few hundred miles since installing it but wanted to pose the question after reading this. Realistically, I will never do a full DOD delete and as much as I would love a BB tune, 4 kids and life will probably prevent me from spending the money on it. Therefore, am I safe to continue using the Range constantly or, a removal and run it a bit and replace?

Thanks!

 

[Dustin Jackson]

Afternoon All!

So I was reading another post where some one stated they ran the Range AFM Disabler and then once they took it out their lifter got stuck. Is this something to be concerned about at all? Would it be good practice to take out the Range device every once and a while to allow the AFM to engage to keep things lubricated (forgive my exact understanding of how the internals work)? I have only had it in and driven the truck for a few hundred miles since installing it but wanted to pose the question after reading this. Realistically, I will never do a full DOD delete and as much as I would love a BB tune, 4 kids and life will probably prevent me from spending the money on it. Therefore, am I safe to continue using the Range constantly or, a removal and run it a bit and replace?

Thanks!

@jdwood1111 I would recommend that you either use AFM like the factory intended or you disable it, I would not recommend switching back and forth.

For $50 there is a guy that will tune your ECM for it to permanently turned off much more affordable than the blackbear tune. I recommend this more than the Range product especially if you have to smog occasionally.

If I could go back in time.. I would tell myself to skip the Range AFM disabler entirely and go with an ECU AFM delete or tune and I might have saved my lifter and cam but here we are. I wouldn't recommend turning AFM back on after having it disabled for a period of time. This all happened to me around 170,000 miles.

Also.. part of the problem with getting the blackbear tune is you have to remove the AFM disabler so that you can log data for the Blackbear tuner and this is another moment in time when my motor had to reactivate the AFM lifters. You might be able to get around this by using OBD2 connector splitter. Sorry a bit off topic.