i am looking into buying an 84 gmc jimmy 4x4 with a 6.2l diesel non turbo , and a 700r4 transmission . I have already heard it is a slug but how are the life expectency of the engine and tranny?I would also like a little info on the rest of the truck.I grew up in the backseat of a 72 k5 but i dont know how the 80s ones are?any opinions or advice would be greatly appreciated.The one im looking at has a straight body,and 70,000 original miles.but it dose have paint pealing.the asking price is 3200.what should i offer him?

 

The motors and trans are BULLET proof man. But they are slugs. I've always known them to be diesel-eaters too.. not very efficient. No noteworthy aftermarket either.

 

dang slow and guzzlers thats an annoying,but glad to hear you've known them to be reliable.

 

Trust me they are sloooow. And I've heard they suck down diesel like crazy (I know the ones in the Army LOVED to eat diesel). But yes the trans and old detroit motors will last forever if they are maintained.

 

the ones in the army suck fuel is because they have turbo 400 that only has three forward gears. 4.56 gearing whichs is very short and makes it rev high, and they wiegh a lot more than the averge civillian vehicle that has a 6.2. depends on the gearing and what tires you have they can become very fuel efficent like 22-24 mpg on the highway. try that in a turbo'd 6.5 truck. yeaah there slow but yes they will live a long time if maintained.

 

Yes this is true most things that have the tiny detroits ahead of them have the 3spd autos.. I figured that was what all the 6.2/5's of the year were coming with? Also as far as the gearing, couldn't tell you.. but I'l ltake your word for it that it was 4.56. What did most civie trucks come with?

 

With it being a civilian and having a 700 in it it should do good on fuel. The military would run a lower gear than the civilian which would most likely be in the 3.xx. They also weigh a lot with all the armor, bullets, guns, grenades and other crap you don't need unless you live in Detroit. My 6.2 get's in the mid 20's. The engine should last along time but the trans I am not a huge fan of. If you aren't pulling a trailer or ragging the crap out of it it should be fine.

 

Ahhh and there he is . The detroit 6.x guru

I like the Detroit, MI comment :P

 

Now you know sooner or later I would come home and find you posting on questions about a 6.x and have to join in the fun. You just under estimated how long it would take. You must have forgot I drive a 6.5 do you know how many hours you have to work to earn enough money to keep one of them on the road? I ain't the only guru on here woody is to but I think he probably learned about them the right way buy learning from others experiences. I on the other hand learned buy lots of bad ideas over and over again. For instance did you know you can run a 6.2 on gas dumped down the intake for at least 30min's but you will bust pistons.

I figured someone would like my driving a Detroit through Detroit.

 

hahaha what a guy. You kill me. I figured you would have caught my post sooner than you did, on the 6.2/5's!

No. No I did not know you can run a 6.2 on gas for 30 mins