Teach Me 1999 GMC Suburban 1500 4x4, may look at one this evening.

So the title says it all pretty much. What are the problem areas to look for?

Edit-OK maybe not all

Dexcool.

if everything works, it will probably keep working for a long time. Price? mileage?

Pay attention to how it shifts. Being a 1500, it'll have the 4L60e. With maintenance, they can last. With maintenance.

Diesel or gas? The 6.5TD has its own set of problems, but I've had pretty good experience with mine. I usually just assume they're gas unless its mentioned otherwise.

They're great trucks. The only thing I'd rather have is a newer one at this point.

Did you buy it?

In reply to Powar:

I believe the 1500 6.5TD is a unicorn - I actually know of one around here, but all the other diesels I've seen are 2500s. If it is a diesel the good news is that that got the 4L80e.

I have one. 4wd solenoid is weak. Rear brakes are drums. At this age they may have had a lot of deferred maintenance (mine go a battery/radiator/AC compressor when I bought it) Otherwise they run virtually forever.

The title actually doesn't say it all

1999 was a crossover year, I believe you could still get the older GMT400 "classic" body style. Pretty big difference between the GMT400 and GMT800 trucks.

HiTempguy wrote: The title actually doesn't say it all 1999 was a crossover year, I believe you could still get the older GMT400 "classic" body style. Pretty big difference between the GMT400 and GMT800 trucks.

OK it's a gmt400 classic style body, It's a 350 so I think that makes it a vortec 350 by 99 right? , I'll check tonight as I'm going to meet the guy after work. I know the bottoms of the doors are a little crusty but underneath looked fairly clean given age and living up in the northeast.
Are the driveshafts a common issue like the later trucks? Front diffs like to eat themselves? Certain areas that hide rusty problems? Are rear disks a pretty easy swap with 2500 just parts? Other bigger brake improvements easy?

It should be the Vortec 350 in 99. Rear discs from a 2500 won't just swap, rear axle is 8-lug while 1500 is 6-lug.

check the frame if the rig is from the rust belt.

common rust spots are rear leaf hangers and the cab mounts.

I have a 99 2500 with the 350 vortec motor. It is a tank and tows well (but slow on hills). The drivetrain is pretty bullet proof. Mine is starting to have minor issues like sagging door hinges, broke an exterior door handle.

The 1500 has the 4l60e trans which does not have a great record for longevity but most trans shops rebuild them all the time and they're not too pricy.

I like my 2500 for extra capacity and beefy running gear but you really can feel that extra 1000lbs.

all 99 suv's are old body style.

now that's out of the way, i had a 94 and loved it. however, it was from a climate with salt water prior to being in ohio, and they towed a boat. so most of the truck was beautifully clean, but the rear bumper fell off and the frame rotted above the hitch.

treeeee fiddddy!

Do the normal old-school checks: look at the trans dipstick and smell the fluid. The engine is a no-brainer. Its a 1-piece rear, roller cam, vortec headed 350. The worst that happens is that the heads develop a small crack near the exhaust valve seat, or the left rear intake water gasket leaks.

You'll hear stuff about the awful factory "spider" injectors, but they have proven extremely durable. Most of the guys who complain about them do so because they aren't upgradable to bigger ones.

Yes, flush the dexcool. It is evil orange jello. Seriously.

Driveline is robust. Usually the first thing to go is something about the 4x4 solenoid system. Next will be a pinion bearing at 300k. Then the transfer case chain will get slack at about 400k. Rebuilds on the 4L60E will likely be every 140k.