2008 Denali XL - 185K miles....when will the "big bill" come callin'?

[BG1988]

Currently I have no slippage in the transmission and the motor isn't overly noisy. It doesn't really leak oil as I fixed that last time I had the oil pan off. However, it does burn about 1.5 quarts between changes, which I can't imagine isn't bad considering it's as old as she is.

you can Stop the oil burning now.. if you want to..


not changing your oil enough every 7-9,000 miles and buying garbage fuel have you as well ??

no wonder your burning oil


I see you replaced the Cats twice that is a bit odd since those last like 140-170k miles or more



If you see my repair log it says:

Map sensor $40(installed my self) 90K
Air filter $18(installed my self) 87K
Oil change inc filter and labor $43 at 86k
Oil Change inc filter and labor $53 90K(bought 2 5qt bottles as a single qt was 10$
plus DIY fluid inspections every 500 miles



start changing the oil every 4k miles it will clean out the system slowly(as not to dislodge big chunks)

my Hybrid Vortec 6000 does not consume oil, AFM works, if taken care of.. because it had frequent oil changes in it's lifetime


Dirty oil wears out the seals and will make the burning oil happen at a faster rate.


basically becomes a run away issue .. I had a real heated debate about it with someone on another forum he was pretty upset when i told him he ruined his engine doing 7-9k oil changes.

he claimed to have been using it for towing and doing 9k oil changes

 

[r870]

My transmission died on my 2011 right at 185k, back in April - $4500 to replace but been running strong for the 10K miles since. From what I've seen they seem to last 150-180K on average.

Someone else mentioned the rims flaking and needing to be replaced - started happening on mine as well but it's more of a cosmetic issue at this point so no plans to replace them unless they get super bad.

 

[swathdiver]

My transmission died on my 2011 right at 185k, back in April - $4500 to replace but been running strong for the 10K miles since. From what I've seen they seem to last 150-180K on average.

Someone else mentioned the rims flaking and needing to be replaced - started happening on mine as well but it's more of a cosmetic issue at this point so no plans to replace them unless they get super bad.

Do you remember what specifically failed on the transmission Chase?

 

[r870]

Do you remember what specifically failed on the transmission Chase?

It seemed to be the torque converter, but I wasn't able to dig into it enough to figure out exactly what went bad in it. I was out of town towing a trailer back home when it died, and had to drop it off at an unfamiliar transmission shop for the fix. He said that when he drained the fluid it was full of metal, and that usually the torque converter is what goes on them.

Basically when I was driving the engine would just randomly rev up super high without actually putting any power to the wheels.

 

[wjburken]

Someone else mentioned the rims flaking and needing to be replaced - started happening on mine as well but it's more of a cosmetic issue at this point so no plans to replace them unless they get super bad.

I replaced my OEM chrome rims on my ‘07 at 185K because the flaking chrome was causing two problems. 1) I would get slow leaks every 15K to 20K and would have to get have to have the rims cleaned up and polished at the beads. 2) When I would wash them by hand I was afraid I would slice my hand open on a pieces of chrome that lifted.

Went with a set of American Racing rims from Tire Rack. Needed new tires as well so had them shipped with tires mounted and balanced.

When we traded it in for our ‘08 I had them swap the rims because the ‘08 was set up with 17” rims and I didn’t like that.

The ‘13 has the chrome so we will see how they hold up.

 

[JayMcB]

I traded my 2008 in 2014 on a leftover 2013....same vehicle, just the AFM motor on the '13.

At the time of trade (189k), it needed tires, balljoints, airbags in back, it's second set of brakes, trans cooler lines and the transmission was starting to make a bang between the 2-3 shift. They offered me 3k in trade, which in retrospect I should have not done and kept it to play with. The big bill may be coming soon, but it is (was) better than a new payment.

As a followup, the AFM cam crapped out on the '13 last summer at 135k, and GM wouldn't help, so I put a range AFM module in it and traded it in. Upgrading to a newer year isn't a powertrain upgrade...

 

[muncie21]

I recently traded my '09 Denali for a '14. Same trim and color, except the '09 wasn't an AFM motor.

Nothing wrong with the '09 just a little bit of body rust from winters here in PA/OH. If I had more room in the garage I would have kept the old girl as a back up vehicle. 100% reliable, didn't burn a drop of oil (even at 135K when I traded) everything worked as it should. Only issue was the exhaust bolts. Several had broken, so she had a bit of a 'tick' until the engine warmed up. That was going to be my next maintenance item, had I kept it.

 

[iamdub]

Fantastic information Trevor and thanks for sharing. I run a very similar log on Excel but it is only 2 years long so far.

If you're getting tired of the truck, replace it. If you want to keep her driving her, then keep fixing what needs to be done, including the transmission and engine and axles and transfer case when those days come.

I agree with this. I'd like to add that you should stop basing your oil changes by the Oil Life Monitor and stick to a more frequent and regular schedule. Or, since the OLM does calculate based on valid factors, change the oil when it's around 30%-50%, assuming you continue to use quality, full-synthetic oil. I'd also highly suggest you get a catch can. For the money and design, I really like this one:

https://www.amazon.com/Sporacingrts...=B07JQKHW9W&psc=1&refRID=K6RTT9T0Y2R1BVQ8K0TB

Add a stainless scrubber pad and better hoses and you'll have a ~$30 investment that could save you thousands.

 

[szyg6h]

No AFM, this is an L92 motor.

Trevor, how's the gas mileage, still basically the same?

No AFM, this is an L92 motor.

Trevor, how's the gas mileage, still basically the same?

Does this mean-
it is pre-AFM?
Or L92 is an engine that does not use AFM but other 08s would?

 

[swathdiver]

Does this mean-
it is pre-AFM?
Or L92 is an engine that does not use AFM but other 08s would?

In 2008, there were other engines with AFM, the LY5, LC9 and LMG. The L92 never had AFM in its two years; 2007 and 2008.

Now let me throw a wrench into that statement for you. The very earliest L92s, those engines made before April of 2005 had AFM hardware but it was not active in the tune.