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

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Mr T

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Folks:

As subject line says, my 2008 Denali XL has 185K miles. I've done the majority of the work on it over the past 8 years. I bought it with 52K miles in 2011. Been a good ride for us, but not the lease expensive to drive. I've put $6,269 in "Maintenance" and $7,079 in Repairs. I'm providing a link to my google sheet that has my entire maintenance record I've kept--only if any of you are interested in what I've done and HAD to do since 2011. I say that because some of the repair didn't HAVE to happen (like repair of fender and paint the nose).

My question is, and I know there isn't just ONE answer.....when do you folks think I will have to repair/replace the transmission and/or motor?

I'm really thinking I should consider selling it before a big cost of 5 to 7K comes in with a replacement of either.

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.

Thoughts?

LINK -->
https://docs.google.com/spreadsheets/d/1bLAM4oCTOxOvUapawaWsc0BVxPgqUZ0magi0H44BIuA/edit?usp=sharing
 
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wjburken

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Is it AWD or 2WD?
How hard do you drive it?
Mostly highway?
Do you tow a lot?
 

swathdiver

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Folks:

As subject line says, my 2008 Denali XL has 185K miles. I've done the majority of the work on it over the past 8 years. I bought it with 52K miles in 2011. Been a good ride for us, but not the lease expensive to drive. I've put $6,269 in "Maintenance" and $7,079 in Repairs. I'm providing a link to my google sheet that has my entire maintenance record I've kept--only if any of you are interested in what I've done and HAD to do since 2011. I say that because some of the repair didn't HAVE to happen (like repair of fender and paint the nose).

My question is, and I know there isn't just ONE answer.....when do you folks think I will have to repair/replace the transmission and/or motor?

I'm really thinking I should consider selling it before a big cost of 5 to 7K comes in with a replacement of either.

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.

Thoughts?

LINK -->
https://docs.google.com/spreadsheets/d/1bLAM4oCTOxOvUapawaWsc0BVxPgqUZ0magi0H44BIuA/edit?usp=sharing

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'm just shy of $2K in repairs and $3500 in maintenance. I have Magnaflow cats too, so I'm looking at about 57K before they give up the ghost maybe, good stuff.

Do you remember the earlier battery brands? First went almost 57K miles, 2nd went just over 71K miles and the 3rd last just over 43K miles.

I've also created an aging showing mileage, engine hours and time for the replacement parts and repairs.
 

adventurenali92

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The transmission will give at some point. That’s just vehicles. As to when it goes bad is up to how you maintain it. Regular interval fluid and filter changes seem to be the key to what keep these transmissions going strong. But I’ve read mixed things on that so don’t quote me on that haha. I’d be less concerned with having to replace the engines. They’re well build and given the right maintenance can go along way from what I’ve seen here in the forums. Does your motor have the AFM system? From what I understand that causes some oil consumption issues. And shutting it down can eliminate that and add to longevity of your motor.
 

swathdiver

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The transmission will give at some point. That’s just vehicles. As to when it goes bad is up to how you maintain it. Regular interval fluid and filter changes seem to be the key to what keep these transmissions going strong. But I’ve read mixed things on that so don’t quote me on that haha. I’d be less concerned with having to replace the engines. They’re well build and given the right maintenance can go along way from what I’ve seen here in the forums. Does your motor have the AFM system? From what I understand that causes some oil consumption issues. And shutting it down can eliminate that and add to longevity of your motor.

No AFM, this is an L92 motor.

Trevor, how's the gas mileage, still basically the same?
 
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Mr T

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No AFM, this is an L92 motor.

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

Hey, James. Gas mileage is the same--if not better ;-) Meaning we drive softer. On long haul trips, I get 18 to 19. Lot of around-the-town "soccer mom" driving gets 14.
 
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Mr T

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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'm just shy of $2K in repairs and $3500 in maintenance. I have Magnaflow cats too, so I'm looking at about 57K before they give up the ghost maybe, good stuff.

Do you remember the earlier battery brands? First went almost 57K miles, 2nd went just over 71K miles and the 3rd last just over 43K miles.

I've also created an aging showing mileage, engine hours and time for the replacement parts and repairs.

James: I really like your idea of adding engine hours when I did something. Just another easy data point.

I should have recorded battery brands. Chance are they were Walmart brands since I always thought batteries were mostly the same--until you get the type that look like a 6 pack of soda.

BTW, my Magnaflows didn't really hold up well. I've often wondered if my Cat/O2 sensor issue I've had was more cause by improper fuel flow/etc/ than bad cats. That was the largest combined expense. Figure it, I've put two sets of Cats on this rig. That's nuts.....maybe not. I'm just used to my Hondas as I've never done a cat replacement on them and driven them to the moon and back.
 
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Mr T

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Is it AWD or 2WD?
How hard do you drive it?
Mostly highway?
Do you tow a lot?

Wife drives it a bit more demanding than I; however, overall, we are not bad. Never had teenage morons doing damage. I've taken it off-road sometimes, for fishing or camping. Nothing too drastic. I'd say 60/40 Hightway/city.

Tow? Only a boat twice and light tailors occasionally to haul yard waste to the green dump. So not really much.
 

swathdiver

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James: I really like your idea of adding engine hours when I did something. Just another easy data point.

I should have recorded battery brands. Chance are they were Walmart brands since I always thought batteries were mostly the same--until you get the type that look like a 6 pack of soda.

BTW, my Magnaflows didn't really hold up well. I've often wondered if my Cat/O2 sensor issue I've had was more cause by improper fuel flow/etc/ than bad cats. That was the largest combined expense. Figure it, I've put two sets of Cats on this rig. That's nuts.....maybe not. I'm just used to my Hondas as I've never done a cat replacement on them and driven them to the moon and back.

The original cats are high quality and made to last a lifetime. However, a fuel system problem can quickly wreck them as was the case with mine. Someone welded in a cheap Chicom cat around the time the AFM system was overhauled and they both failed by 122K miles (12K miles after AFM work). So we put the Magnaflow cat and y-pipe on and they've been great ever since.

Crawled under a few days ago and was a little alarmed at how rusty the stainless pipes are; as is the rest of the factory system. Guess a new system is in my future if we don't stop driving this thing on the beach!
 

wjburken

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My 07 went 300K. My transmission needed replaced at 160K-$4000. Transfer case at 260K-$1800 (should have done it at 240K), rear diff rebuilt at 260K, front diff replaced with low mileage used one. Replaced front drive axles at 220K. Replaced chrome rims at 180K due to severe chrome flaking thanks to Iowa winters a road salt.
 

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