Suburban/Yukon known issues list to fix before it's an issue

[vanroth]

Serp belt
Idler pully/tensioner
Fuel Pump
ABS Computer reflow/resolder
Front wheel bearings
Rear diff seal
MAF (stupid driver problem -- no, not this driver!)

I have over 270K on my 2001 Tahoe and the above are the only things that I've had to do to it. Diff seal went out in less than 50K, but most of the above I did not do until past 200K. Even better, all of the above issues gave me plenty of advanced warning and never left me stranded. My heater control valve hasn't failed, but I may do a preventive on it -- it was a pain when my Astro's went out. Not only did it leave me stranded (a few miles from home), but the repair required an extended hose clamp removal tool to swap out.

 

[rad]

Regarding the upgraded fuel injection spider for the Vortec engines, the GM part number for the complete upgrade kit for the 5.0L and 5.7L V8 engines is PK93441235. This gets you the spider and a set of new gaskets for the intake plenum.

 

[1stDeuce]

For that era of truck, if the pump is noisy, it probably needs replaced. If it's not noisy, just keep running it. Trick for "dead" pump: If it starts, then dies, or just won't start, and you don't hear the pump run for a few seconds when you key on, your pump has probably stopped. If that happens, you can almost always get it running again. Key off. Crawl under the truck with something to bang on the bottom of the fuel tank. (rock, piece of 2x4, your boot) Start whacking the bottom of the tank and have an assistant crank it over while you whack. That'll normally jar the brushes back into contact, and the pump will run again. As long as you don't shut it off, you're completely good. Even if you do shut it off, it'll restart just fine 99% of the time, over and over. But it's still time to replace it if you have to use that trick. Run the tank down to empty, then run it some more. (Empty is more like 4~5 gallons left for most GM trucks)

I have a free one for you too... Shift the T-case a few times a month. If you don't, the encoder gets gummed up and then it won't shift when you need it most. You don't really have to drive it, just shift in and out of 4wd a few times a month. (Best done while driving slowly, just to sling some oil around the diff.) Shifting to low range occasionally is good to do too if you ever plan to use it.

I wouldn't worry about wheelbearings unless you hear them. Generally, if you keep to stock wheel offsets, and stay out of really deep water, they last a LONG time. (I've gotten over 200k out of two different 3/4 ton trucks now, and Dad has done the same with two different 1/2 ton gm trucks running snow plows.) There are always the infant failures, but if you cleared 100k, you're probably good for another 100k+.
Chris

 

[superbuickguy]

flush the cooling system, if the coolant hasn't been flushed, a brown crud will build up in the block leading to overheating issues.

 

[barefoot boy]

The front wheel bearing problems I had were on a GMT800 2500HD series truck. My '95 GMT400 K1500 went 275k miles with no wheel bearing issues. A number of people I know with GMT800 trucks have had numerous front wheel bearing problems. Both of my trucks had factory wheels and were used in the same type of service.

 

[1stDeuce]

Hmm. Interesting. I'm running an '06 2500 (GMT800) now, and just passed 200k on the factory front wheelbearings. The other truck I had was a '96 2500 (GMT400) and made 300k before I sold it. Wonder if there was a supplier problem in the early GMT800 years?? Either way, they make noise before failing, and give you plenty of warning. Unless you're running mud tires, you'll know when it's time to replace them!

And I'll second the cooling system flush. I have been running Prestone "All Makes and Models" in all of my vehicles. That way if I don't get the flush complete, it's not a problem, and if I have to add something else in an emergency, also not a problem.

 

[Oobray]

I can speak to the T-case fix. Not a week after I bought by Yukon XL I was waiting on my wife to get done shopping and of course I had to mess with stuff. I pushed the 4wd button and it got stuck. The part was around $250 I think. Be really, really careful when installing the new part!! All the bolts will line up and screw tight even if the plunger isn't exactly lined up with the T-case. Ask me how I know this! Broke the housing on the actuator and I had to basically take all the new parts and swap them in to the old housing. Turned a 2 hr job in to about 7. Good times :clapsmile

On a really cold day recently I could hear the fuel pump. If it lasts till spring I'll be replacing it.

 

[Nullifier]

Not sure if I missed it but I didn't see the knock sensors listed. On the ls based motors they are under the intake manifold and down in a recess. Water gets in the recess and rots them out. You will need 2 knock sensors, the wiring harness pigtail, intake gasket, intake manifold bolts since they are one time use only and some hitemp rvt. There are tons of articles on the web for it. I had to do mine a few years back. Good news is its a driveway repair if you have a torque wrench and half a day.

 

[rayra]

Any input or advice on a '02 4L60-E trans with 116k that seems to be slipping at takeoff? Cold or hot, starting to slip a little, almost like a fluid pressure issue.
When I bought it just before Thanksgiving the fluid was fresh / cherry red and clean smelling, unfortunately. Denied any info from it. And not even sure the right fluid was in it. I'd done all manner of other 100k type servicing, brakes, engine oil etc. But elected not to mess with trans fluid / filter, the cooling system, or even do any sort of heavy degreasing on the engine on the premise I might trigger the very sort of troubles (storied 5.3L intake gasket leak and such) I'd hoped to postpone.

I'm only about 1100mi into my ownership and noticed the slipping after a recent spate of freezing weather. Now it seems to occur both cold and hot. If I'm real easy on the accelerator, or have only let off it for a very brief time, doesn't occur. But after a red light or give it more than a 1/4 throttle and it revs a bit before the trans seems to take hold.
Don't have a lot of money to throw at it right now, blew my funds buying it. Thinking to do a straight fluid drain and replace, using proper fluid in the hopes of forestalling more trouble. Any advice?
I need to get an OBDII reader and check for codes. No idiot lights or 'driver info center' notices.

 

[rad]

Buy or borrow an OBDII reader and check for codes. There are trouble codes related to the transmission that won't trip the check engine light. If you have any make a note of them. Whether you have any or not, get the transmission flushed. Have this done somewhere reputable or at a dealer so you know it will get the right fluid put in. Don't got to one of those quick lube joints for this. If you found codes earlier clear them and see how things go. If the problem continues check for codes again. The problem may likely just be a failing solenoid, especially if the problem is very consistent

Your problem sounds almost exactly like a problem I had with a 2004 Buick Century. The check engine light stayed off, but checking for codes revealed a P18xx code that was related to failing solenoid. $350 later it was good as new.

 

[Oobray]

Another to add that I've read is common. I just replaced the blend motor actuator on mine. Replaced two actually. Replaced the motor that controls the 'mode' and the one that controls hot/cold blend. The mode is located about 2 o'clock to the gas pedal up in the dash, the heat is under passenger side. Both were a PIA to get to, but not that expensive. The mode motor went out on me during a snowstorm causing me to lose defrost mode. Which of course caused the snow to start freezing on the windshield and I had to stop every 5 miles or so to scrape the windshield. Not fun.