I apologise if I have posted this in the wrong spot, I am new. I am looking at purchasing a 1999 3500 GMC Diesel. I know nothing about diesels, so Im not sure what to look for. As far as mileage, whats too much?? Its a 4x4 so should I be concerned about the transmission and transfer case?? I guess Im just looking for some pointers as to whether this truck could be a lemon. Was the '99 a decent year for this truck?? Oh, and I was wondering if the GMC diesels are turbo'd like the Dodge??

We would need more specs to give any pointers, auto? miles? has it towed?
But, it will be a turbodiesel. It does not put out the kind of power that a powerstroke or cummins are capable of. But it can be a solid motor once you are educated about the shortfalls. All motors have them....Is it a lemon..?
can't tell yet...:cool:See if you can get the VIN number and get it run by a GM dealer to check the service history to get an idea of what has been done. Good luck with your Truck....
BTW welcome to the forums....

Well Ill try and get some more info, such as the VIN and mileage. But as far as a '99 Diesel goes, what would too much mileage be??Also what would have to be done to get the 6.5 running with a Cummins?? My girlfriends family are Dodge fans, and her father has a Cummins. I dont want to fall short against a Dodge CheersGodti

250,000 ~ 300,000 miles seems to be the typical life expectancy of a well kept 6.5. Possibly more, definitely less if it's been abused.

The 6.5 will never, ever run with a Cummins. Sorry.

The 6.5 will never, ever run with a Cummins. Sorry.
Even with mods?? Could you tell me the stock HP and Torque??

You need to be realistic. I have both a '95 Tahoe and a '99 Burb. I find the two vehicles reliable, powerful, unique and YET they are inexpensive to maintain (so far). I did NOT purchase them because I wanted to win a power contest. I purchased them because I was buying used vehicles (didn't want to pay the depreciation), and I primarily needed people haulers that could go off-road and tow things. If I needed something that had the capacity to go to 1000 ft-lbs of torque, I agree - you need to get a newer engine design, such as the common-rail-injection diesels in the newer Fords/Chevy/Dodge line. Don't think you can pump up a design from the early '90s that was never spec'ed to deliver 500-600 ft-lbs stock like the new ones are.

Here's an analogy: It's like the difference between a 3/8" and a 1/2" ratchet. If you put a longer cheater bar on the 3/8", you'll get more out of it, but the 1/2" will probably out-do the 3/8" in stock trim, and if you put a cheater bar on it, you'll get even more. If you put too much stress on the 3/8", it will break in a hurry, and you may still not be as strong as if you simply bought the 1/2" to start with.

AFAIK, the '99 had around 199HP and 400Ft-Lbs of torque in stock trim.

Sincerely,

Rob :)

Stock horse power is 195. Torque...I'm not sure. They do make high performance chips(ECM's) that are said to deliver up to 80 additional horses as well as alot more torque...This is the route that I am taking.I recently installed a 4" exhaust and felt a seat of the pants difference. The 70 horse (chip) and turbo master should be here in about a week. I will let everybody know how it goes. I heard(just heard) that it would be just shy of a stock Dodge diesel.Take that however it sounds. I am new to this as well.This site and all it's participants are a GREAT combined knowledge on these motors. The more I read, the more I learn.(And the more trouble I get into with the wife):confused:

Turbo Tahoe, Good job on your reasoning. I, too, wonder why guys buy a 30-30 rifle and try to make it into a 30.06?? If you wanted a 30.06, why didn't you just buy one!

I have a friend who traded in an early '90's Ford 1-ton dually after three trans failures in 6000 miles. He bought a Freightliner (older cabover) tractor to tow his 33' fifth wheel stock trailer. He says he gets comments about how "Yer trailer shrunk" from the truckers. He loves it. Gets better mileage than the Ford when towing, has a/c, sleeper cab, etc. He says, "If you need a truck, get a TRUCK!

I have a 98 with the 6.5L, I've had it about a year, and am not to impressed with it. everything stock. 315/75/16, 3.73's, 4l80e, auto, 84k. What would best recommendation be for modification as far as bigest bang for the buck. Do the reprogrammed ecm make a big enough difference to justify a $550ish cost? Exhaust? I had an 01 Dodge dually prior and would definately out pull two of these anyday. Any suggestions would be great. Thanks!

I have a 98 with the 6.5L, I've had it about a year, and am not to impressed with it. everything stock. 315/75/16, 3.73's, 4l80e, auto, 84k. What would best recommendation be for modification as far as bigest bang for the buck. Do the reprogrammed ecm make a big enough difference to justify a $550ish cost? Exhaust? I had an 01 Dodge dually prior and would definately out pull two of these anyday. Any suggestions would be great. Thanks!

I highly recommend that you look at the FAQs and read Turbine Doc's recommendations for more power.

Sincerely,

Rob :)

Now SD we know that ain't wholly accurate, against a modded Cummis, nope 6.5 ain't got it, but vs stock; modded 6.5s can hold their own.

The 6.5 will never, ever run with a Cummins. Sorry.