New to me 2011 Yukon XL Denali

[jdwood1111]

@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.

Thanks for the reply and opinion. I agree just wasn’t in the cards but I could not find any other tuners on the site after looking so if you could point me in the direction of whom you be referring too that would be fantastic! I have called a few tuning places around here and no one knows who tunes GMs but I have a couple more places to call.

I wasn’t planning on taking it out often just ever once and a while. I’m in PA so smog once a year which for me won’t be for a while.

 

[Dustin Jackson]

@jdwood1111 Here is the link, I haven’t tried it myself but I trust @iamdub recommendation: https://www.lt1swap.com/afm_delete.htm

 

[jdwood1111]

So last minute we decided to take the Yukon on our trip to FL instead of the odyssey. I checked all fluids, got my emergency kit ready, aired up the spare and we are about 500 miles in as of tonight! Longest time driving the new truck since I bought it! Truck performed very well on the highway! With the range device I’m getting 16.3 mpg with 4 little kids, wife, small dog and back packed pretty good so I guess I’m good with that considering I was 70-80mph the whole time.

Here is where I’m a little concerned. Transmission at low speeds. Temps never went above 183 and shifts when on the highway we’re good. No hesitation in up or down shift when passing etc. However, low speed and mostly I think 1-2 and 2-1 are not feeling great. Could be 2-3 and 3-2 but hard to tell with kids screaming. Clunky is the best word. I know I need to do the fluid and filter but is this a sign of something worse? In and out of reverse seems a bit “strong” too. Fluid did not smell burnt and still had slight red hue to it.

Miles in the truck are 92.8k for those that haven’t been reading.

 

[avalonandl]

You really need to check the fluid and have it flushd if not bright red.

 

[Dustin Jackson]

So last minute we decided to take the Yukon on our trip to FL instead of the odyssey. I checked all fluids, got my emergency kit ready, aired up the spare and we are about 500 miles in as of tonight! Longest time driving the new truck since I bought it! Truck performed very well on the highway! With the range device I’m getting 16.3 mpg with 4 little kids, wife, small dog and back packed pretty good so I guess I’m good with that considering I was 70-80mph the whole time.

Here is where I’m a little concerned. Transmission at low speeds. Temps never went above 183 and shifts when on the highway we’re good. No hesitation in up or down shift when passing etc. However, low speed and mostly I think 1-2 and 2-1 are not feeling great. Could be 2-3 and 3-2 but hard to tell with kids screaming. Clunky is the best word. I know I need to do the fluid and filter but is this a sign of something worse? In and out of reverse seems a bit “strong” too. Fluid did not smell burnt and still had slight red hue to it.

Miles in the truck are 92.8k for those that haven’t been reading.

@jdwood1111 Glad to hear it's going well man. I just took my Tahoe on a 1,100 mile road trip immediately after doing a cam and lifter swap so I know it can be nerve wracking.

Can you elaborate on your concerns of the transmission at lower speed? I don't know what you mean by clunky

 

[jdwood1111]

@jdwood1111 Glad to hear it's going well man. I just took my Tahoe on a 1,100 mile road trip immediately after doing a cam and lifter swap so I know it can be nerve wracking.

Can you elaborate on your concerns of the transmission at lower speed? I don't know what you mean by clunky

Unfortunately it was very hard to tell with all the kids in the car but basically when I was I stop and go traffic, I noticed an occasional hard shift mostly on the 3-2 or 2-1 shifts. The upshifts didn’t seem as bad. However, since this post I had what feels like a slip happen twice. This was when cruising around 30mph +\- in what I believe is around 4th and then I stepped on it would shift fine into 3rd but then seem to not really want to go in to 2nd. The first time I may have left off the gas just as it wanted to shift but the second time I did it trying to reproduce it, I thought it did it again. I am hesitate to try it again now. When driving it like a grandpa it seems fine. I unfortunately have nothing to compare it to as this is my first ever truck and GM vehicle except my first car which was a 1989 Z24 cavalier, which I loved! Lol.

When I get back from FL I am either going to do the fluid myself or have a transmission place do it and take a look/drive. It’s a second vehicle and upon our arrival home won’t be used much so I have time to make an educated/long term decision.

Edited:
So I just check the fluid again and while I can’t really read the level well but the color looks quite good to me! (See pic)This would be consistent with the transfer case fluid I changed which was also still quite red. Maybe the previous owner changed it and just doesn’t show up on the Carfax! Either way I’ll still do it just in case the filter was not changed I suppose?

 

[Dustin Jackson]

Is this a 4 or 6 speed transmission?

 

[jdwood1111]

Is this a 4 or 6 speed transmission?

6l80, 6 speed.

 

[Doubeleive]

if you are lucky you can just throw a rebuilt valve body/techm in it and cross your fingers, it's not a super easy fix like the 4l60's are.
not sure what he is working on there but I think you would need to drop the exhaust also

 

[Dustin Jackson]

6l80, 6 speed.

I do not have a 6 speed or know much about it