Army Truck

[ARB-XJ]

6.2L Diesel Chevy pick up, friend has one for sale for real cheap and isnt beat up and run good. My question is could this be used as a tow rig? I tow the jeep about 8 times a year, an about 60m each way to wheel usually.

 

[GrimmJeeper]

I don't see why not, as long as it's not an s-10 with a diesel in it or something

 

[87manche]

the 6.2 will be lucky to get itself out of the way, you'll get there, just slowly.

 

[rmm727]

alot of those had 4.56 or 4.88 gears in them. front dana 60 and 14 bolt rear. some have govloc's. I managed to get a hair over 20mpg driving to harrisburg in one when I was in the guard. I think you would have something if youd take the turbo 400 out and put an sm465 in there. the auto seems to take alot out of them getting it going.

 

[ARB-XJ]

it has 4.56, not sure about locs though. Its a 3/4 ton, wondering how its gonna pull, has anyone towed with one?

 

[Darky]

What's the model? An M1028 will have 4.56s, Detroit 14 bolt rear, LSD D60 front, and Turbo 400. Usually will have an NP208 I believe. The M1008 is the same minus the LSD up front. Both are 5/4 ton trucks. I had every plan on buying one this year, but cash didn't come through as expected and I had to buy something cheaper. The M1009 is a Blazer and is 3/4 ton with 10 bolt front and 12 bolt rear, or something similar. I didn't pay as much attention to those as my plan was truck all the way. The M1009s will have 3.07s in the axles.

If you're going to swap transmissions, the 700R4 seems to be the way to go. 4 speed w/OD vs 3 speed, and the gear spread is well-suited to the 6.2. One of the guys at 4 Wheeler or 4WOR built one with an SM465 and he recommends against going that route. The gear spread didn't match the power curve very well.

My plan was to buy an M1028, put a 2-4" lift on, trim the fenders and run modified HMMWV 12 bolt wheels with the 37" radial HMMWV Goodyears, find a 6.5 turbo diesel to steal the turbo and manifolds from, and build it to be the ultimate tow rig/recovery/camping truck.

 

[5-90]

What's the model? An M1028 will have 4.56s, Detroit 14 bolt rear, LSD D60 front, and Turbo 400. Usually will have an NP208 I believe. The M1008 is the same minus the LSD up front. Both are 5/4 ton trucks. I had every plan on buying one this year, but cash didn't come through as expected and I had to buy something cheaper. The M1009 is a Blazer and is 3/4 ton with 10 bolt front and 12 bolt rear, or something similar. I didn't pay as much attention to those as my plan was truck all the way. The M1009s will have 3.07s in the axles.

If you're going to swap transmissions, the 700R4 seems to be the way to go. 4 speed w/OD vs 3 speed, and the gear spread is well-suited to the 6.2. One of the guys at 4 Wheeler or 4WOR built one with an SM465 and he recommends against going that route. The gear spread didn't match the power curve very well.

My plan was to buy an M1028, put a 2-4" lift on, trim the fenders and run modified HMMWV 12 bolt wheels with the 37" radial HMMWV Goodyears, find a 6.5 turbo diesel to steal the turbo and manifolds from, and build it to be the ultimate tow rig/recovery/camping truck.

If you get the THM700R4 for a swap, avoid 1987 and earlier - the valve bodies in them have a critical flaw three times out of four, and the only real effective "fix" is outright replacement of the entire unit.

The 4L60 is the same as the THM700R4, but the 4L80 would be a better option. Note that you'd probably have to drag along electronic controls.

I'm not sure if it ever ended up behind the Detroit Diesel (or what the bellhousing pattern on the Detroit is,) but I know there's a double-overdrive heavy-duty full-size truck transmission - the 6L80. Definitely electronic controls, and limited availability, but I think that 4WD variations are extant. The 6L80 has only been out for the last 3-5 years, as I recall.

EDIT - The THM400/3L80 is a Hell-for-strong slushbox, but it suffers from the lack of an overdrive gear. Especially with a Diesel, having at least one overdrive range is helpful.

 

[Ghost]

the 6.2 will be lucky to get itself out of the way, you'll get there, just slowly.

LOL! This. There are a ton of guys on Wheelindixie.com that know a lot about these.

 

[rmm727]

My plan was to buy an M1028, put a 2-4" lift on, trim the fenders and run modified HMMWV 12 bolt wheels with the 37" radial HMMWV Goodyears

Those tires will fit without a lift on stock 16.5 steelies. I have a pic I'll have to find with this combo. All that was done to the truck was the rear of the front fender was lightly trimmed. (very lightly) A warrant officer did this to his truck and it looked really clean. Tires didn't even stick out. He capped where he trimmed by splitting a piece of brake line and brazing it on.

He claimed it made the truck much more tolerable to drive on the highway.

 

[Darky]

If you get the THM700R4 for a swap, avoid 1987 and earlier - the valve bodies in them have a critical flaw three times out of four, and the only real effective "fix" is outright replacement of the entire unit.

The 4L60 is the same as the THM700R4, but the 4L80 would be a better option. Note that you'd probably have to drag along electronic controls.

I'm not sure if it ever ended up behind the Detroit Diesel (or what the bellhousing pattern on the Detroit is,) but I know there's a double-overdrive heavy-duty full-size truck transmission - the 6L80. Definitely electronic controls, and limited availability, but I think that 4WD variations are extant. The 6L80 has only been out for the last 3-5 years, as I recall.

EDIT - The THM400/3L80 is a Hell-for-strong slushbox, but it suffers from the lack of an overdrive gear. Especially with a Diesel, having at least one overdrive range is helpful.

You want the older 700R4s. Mechanical controls, keeps it simple, cheap, and overall reliable. I haven't heard any complaints from the guys who swapped them in place of the TH400. The 6 speed would ricockulously expensive. You'd probably spend more on finding one and getting it installed and working right than you would on the entire truck., not to mention trying to mix a 2007+ auto tranny with a diesel from 1986-...

Those tires will fit without a lift on stock 16.5 steelies. I have a pic I'll have to find with this combo. All that was done to the truck was the rear of the front fender was lightly trimmed. (very lightly) A warrant officer did this to his truck and it looked really clean. Tires didn't even stick out. He capped where he trimmed by splitting a piece of brake line and brazing it on.

He claimed it made the truck much more tolerable to drive on the highway.

That's a big part of why I'd want to run the 37s. With no other mods, they should raise the top speed to 75-80 and make 65-70 a reasonable cruising speed. Plus they'd look pretty sweet and get me out to where I want to take the truck.

 

[5-90]

You want the older 700R4s. Mechanical controls, keeps it simple, cheap, and overall reliable. I haven't heard any complaints from the guys who swapped them in place of the TH400. The 6 speed would ricockulously expensive. You'd probably spend more on finding one and getting it installed and working right than you would on the entire truck., not to mention trying to mix a 2007+ auto tranny with a diesel from 1986-...

That's a big part of why I'd want to run the 37s. With no other mods, they should raise the top speed to 75-80 and make 65-70 a reasonable cruising speed. Plus they'd look pretty sweet and get me out to where I want to take the truck.

The THM700R4 is hydraulically-controlled, as is the mid-generation 4L60 - the 4L60E is electronically-controlled (ca. 1997 or so, I think. Brief research should turn up the transition time.)

There's nothing wrong the THM700R4 - 1988 and up. Just avoid the earlier ones, and you'll be fine. Getting an earlier model is a crapshoot on whether it's going to be any good or not - and if/when it does fail, replace it outright. Units built 1988 and up can usually be repaired effectively, and defects are pretty obvious.

 

[Darky]

My brother's 99 is electronic, his 91, I'm not sure. It seems I recall it being electronic, but I don't remember. Didn't pay too much attn.

 

[lyleorszulak807]

hah I use to have a 86 (I think, been a while) full size GMC Jimmy with the 6.2L diesel. No power what so ever going up any grades, and with towing forget it. Was planning on keeping it and putting a 454 in it (SMOG exempt, YAY!) but ended up selling it.

 

[Darky]

Your Jimmy likely had 3.07 gears or something similar. If he's looking at a truck, the CUCV trucks had 4.56. Should help alot with power.

 

[collkid]

They are still SO SLOW!

Friend had a really nice K5 with that Diesel, he threw a Turbo in and re-geared. My escort would blow it away..... and it had 88 BHP

 

[5-90]

They are still SO SLOW!

Friend had a really nice K5 with that Diesel, he threw a Turbo in and re-geared. My escort would blow it away..... and it had 88 BHP

Throttle response in a Diesel - not great.

Diesels are built for torque, not horsepower.

Deep gearing in the axle makes it easier to go up a grade with a load, but you're not going to do it with any speed (many heavy trucks have two-speed rear axles - and gearboxen with ten or more forward speed ranges. I've seen "gear splitters" for light trucks - either split down for an underdrive for hauling, or split up for an overdrive with deep gearing.)

Besides, that Escort probably masses about half of what the K5 does - another big factor!

A Caterpillar 3208 V8 Diesel is only rated for something like 90-95bhp - but several times that for torque. Bear in mind that horsepower happens at higher crankshaft speeds - and a Diesel won't even get to high crankshaft speeds (it can't.)

 

[Darky]

IIRC, the 6.2 is rated for 140 hp and 250ish for torque. A small block 350 beats it at both numbers, but at higher rpms and higher fuel consumption.

 

[Johnnie Walker]

I believe they are 24V, so you will want to convert to 12V.
Pull the 6.2L Diesel, and put a gasser or CTD in it.
I've always wanted a CUCV as well.

 

[Darky]

My plan was always to keep the 6.2 for simplicity. Fully mechanical, great for when SHTF...

 

[pajeepman]

I had a '83 K-20(3/4 ton GMC 4x4). It had a 6.2 and a turbo 400, not sure of the gearing though. I towed a J-20 on a car trailer once. It did it, slowly though. The 4.56's will help with speed but without an O/D, you won't have a high top speed unless you increase the tire size. They aren't the diesels of today but they were designed at least 30 years ago. Look at all the stuff the old. I met a guy that filtered waste motor oil and ran his truck on a 50/50 mix of that and diesel. Try doing that with a new diesel - fail. I used my truck to pull the J-20 out from where it sat for 6 years, I didn't even realize the back brakes where frozen, the truck just dragged it along without any trouble. They are simple engines, mechanical injection, I read that once the truck is running, you can remove the battery and run the truck without one(no lights, radio, wipers, etc). If there was every a nuclear war/asteriod stike, etc. I would want a 6.2 and a manual tranny. I couldn't tell you what kind of MPG to expect as mine was an export truck and had KM instead, that and it was a pain to fill the tank so I never new if it was full(gauge didn't work). I do miss my old 6.2 truck.