I’m interested on how many miles owners are getting on their 6 liter and 6.2 liter engines.

I have 150,000 miles on my 2008 3/4 ton Suburban. It has a LY6 6 liter engine with a 6L90E transmission. I’m thinking it was of the few 6 liter engines to get a 6L90E. The 6.2 engines were getting the 6L90E’s and most 6 liter’s I understand where getting 6L80E’s. The rear end is a 3.73 limited slip diff. I’ve had the diffs and transfer case fluids changed twice so far, using the Chev dealer’s bulk synthetic fluid and GM friction modifier in the rear diff.

I always used 5-30 100% synthetic oil, usually Mobil 1. I use the recommendations off the oil monitor for change intervals. I drive it a lot in the mountains and use 4 wheel drive a lot in the winter but not on the highway. I tow a 28 ft travel trailer weighing 6300 lbs. When I tow, I use the tow mode and when I’m towing on the highway I drive 60 mph in 4th gear at about 3500 RPM. I feel these engines have torque curves that are at much higher RPM’s than the old school small blocks. I have been towing to destinations about 120 miles away so up to 2 hrs of 3500 rpm driving. The water temp never budges. The trans temp can get to 180 F towing on a hot day. I slow to about 40-50 mph going up steep grades. I’ve had the tranny flushed a few times in the last 9 year’s. The fluid is currently clean and red with no burning. I’ve changed coolant twice so far. Don’t know when it started but I noticed the engine has a cold start tick that disappears at full temp. I might change to 10-30 Synthetic this summer. Some might think I should have done that a long time ago! LOL.

I had to replace the passenger side door lock, the cruise control/ electronic gear shift arm.
The fake chrome is peeling of the inside door handles. Everything is still original under the hood. The transmission cooler lines are starting to wheep at the crimped ends so I plan to replace them. I had a strange moan from the power steering but it all but disappeared when I turkey basted the fluid out and put in fresh fluid.(repeating twice). Also I finally found the 12th zerk fitting and greased it. Yes, the 2008 3/4 ton has 12 fittings for the front end.

I had to replace the oil seals in the rear axles. The rear cargo door still works in the auto lift mode but occasionally binds and makes a banging noise. I’m keeping an eye on the water pump and may replace it next year if it leaks or gets wobbly. My goal is to drive it to at least 200,000 miles before selling it. How many others have reached 200,000 miles and what issues have you had to deal with? I’d also like to hear about the 300,000+ ones and what’s needed to be replaced to get there.

Thanks

S.D.