Hello Everyone,

I'm new to the K5 community and I've spent quite a bit of time reading these forums- an excellent resource! I'd like to ask some questions.
I currently own a '97 Landcruiser and I'm looking to buy an '87-91 K5 Blazer 6.2L Diesel w/ 3.08 gears and 700R4 OD tranny. Planning 31-33" A/T tires, daily driver and occasional mild-moderate offroad use.

1. What price range am I looking at (approx)?

2. Where are some good places to look for one? I'm currently checking: ebay, craigslist, cars.com, autotrader.com, aol autos.

3. Is this combination hard to find (specifically the 3.08 axles with 700R4 tranny)?

4. What are some typical fuel economy numbers with this setup, and how much greater fuel economy does the 700R4 give you over the TH400 tranny?

5. I'm finding a lot of ex-Military M1009 rigs advertised with very low miles (like 15k - 30k miles). Is this listed mileage generally believable or has the odometer likely rolled over? Considering I'd want to make this a DD and add interior upholstery, A/C, convert to 12V, etc. do you think I should consider one of these trucks, or hold out for a civilian unit? What are some pros/cons on these Military trucks?

6. How hard / expensive is it to add A/C to the military (M1009?) or civilian rigs I'm finding without A/C?

7. I've read the 700R4 tranny was revised from '87 onward to be more reliable. Is this true, and are there "best" years for the 6.2L diesel?

8. What is the typical lifetime of the 6.2L engine and 87-91 tranny?

9. What are some common problem areas for these trucks (other than rust)?

10. Is it common to swap a 4L80E tranny behind a 6.2L in order to get a more reliable OD tranny and is this difficult / costly?

11. Is it easy / expensive to add a fulltime NP203 transfer case to this truck, and how much fuel economy would I be giving up to go to fulltime 4WD?

12. I've found some 5.7L V8 gassers in great shape. Is it expensive / difficult to convert these to 6.2L diesel?

13. What were the most common gearings on the '87-91 gassers vs. diesels?

Thanks for bearing with a noob!

Vik

 

1. Really depends on your area and the condition of the vehicle. I would not pay much over $3k for one unless it was in very good condition.
2. You listed them pretty well.
3. I really doubt you would find the 3.08 gears, but does not mean that you could not change them after the fact. I would not want to run those gears and then add taller tires into the mix though.
4. You would probably be lucky to get 15mpg with that setup unless you really babied it. The 700R4 would be better for fuel mileage as it has an overdrive gear. The TH400 does not.
5. It would cost you far more to add the normal creature comforts to an ex-military truck than it would to just buy a regular one in good shape. It can be done, but it is quite a bit of work.
6. Not too bad, but again, it is often more than it is worth as it does take a fair amount of work.
7. A 700R4 behind a diesel would worry me. It is the torque of a diesel that would make me worry...
8. Engine will last a long time with regular maintenance. Transmission... If kept maintained, it can last pretty good as well, but
9. Rust. Well, other than that, not relaly all that much. They were pretty reliable, but not the greatest on fuel.
10. It would be VERY costly as stand alone controllers for the 4L80E (electronic control) are over $600 last I checked.
11. It could be done, but why? If you wanted a more reliable transfer case, you should be looking at the NP205 which is a completely gear driven transfer case. The NP208 or NP241 (depending on what year you choose) are not all that bad in their own right, but you have to be doing some serious wheeling to really need to upgrade.
12. is it a gasser or a diesel? The diesel was 6.2L. The gas engine was 5.7L
13. Most common for these trucks was 3.73 followed by 3.42 regardless of engine choice. If looking at the diesel, then I would suspect that 3.42 was more common than 3.73. 3.08 would make for some lugging around, even for the diesel.

 

swartlkk- thanks for the informative response! I know there was a lot in there...

Some followups:

I've read elsewhere about 20-25MPG being achievable with the 6.2L/700R4/3.08 gears. Is this not true?

Sorry that was a confused bit of typing on my part. I mean I had found some superclean 5.7L V8 gassers and was wondering if it is difficult / expensive to convert the gassers to 6.2L diesels?

 

I have heard of people getting 20-25mpg with the new Duramax Chevy's, but my experiences have just not been that good. There are always trucks that will exceed the norm, but to call that the norm...

As far as converting a gasoline engine vehicle to a diesel, again, it can be done, but there is a lot to it. If you cannot do the work yourself and are not prepared for what is required, it is A LOT better to find the vehicle you want than to try to convert something that is only partially right.

If it is difficult to find a 6.2L/700R4 Blazer with the 3.08 gears, by far the easiest way to go about this is to just find one with the hard to change parts of engine/transmission and regear it.