M1028 700R4 Conversion Been Done?

[Mr. Chevy]

I was wondering if anyone has ever converted a M1028 with the transfer case over to a 700R4? I know the standard truck and suburbans ran 700R4's with a 6.2, but there is different equipment.

I am guessing you sacrafice strength and it can be argued that a good trans shop/guy could help that issue out. I understand, gearing is different, speedo will need to be calibrated, flexplate & possibly starter changed.

Is this possible? Any odd mods? Are there certain years to use parts from? Any success stories? Any horror stories?

Thanks

Nick

 

[Recovry4x4]

It's happened before on many CUCVs just not sure on the M1028. What transfer case does it have? I'm closing on an M1008 and that will be the first major work, it's getting the 700R4. I'm lucky enough to be able to walk across the yard and look at my suburban if I get stumped.

 

[NDT]

You need to search the forums for "NP205", there is a lot of info on this conversion.

 

[Recovry4x4]

Going by memory the M1028 and M1028A3 use the 208 case and the M1028A1 an A2 use the 205 case. I'll have to confirm this.

 

[84cucv1ton]

all the 1028 in my family have a 208. cant use it tho. th400 is a 32 spline 700r4 is a 27 spline i think.

 

[Recovry4x4]

Copied this from the TM. The M1028A1 and M1028A2 do have the NP205 transfer case.


d. Cargo Truck, The M1008, M1008A1, M1028, M1028A1, M1028A2, and M1028A3
1-1/4 ton, 4X4, cargo trucks are. light commercial trucks designed to provide standard tactical mobility and to carry cargo or passengers, All models have a tow pintle at the rear bumper to permit towing of trailer or aircraft. The M1008 can be equipped with a troop seat kit for eight personnel. The M1008A1 Includes a 100 amp/28 v communications kit. The M1028 is equipped to accept a 100 amp/28 v electrical system and S250 communications shelter and a communication kit. The M1028A1 ls equipped with a New Process 205 Transfer Case which allows for the addition of a power take-off (PTO) unit. The M1028A2 is an M1028A1 that has been converted to rear dual wheel configuration. The M1028A3 is an M1028 which has been converted to rear dual wheel shelter carrier configuration and is equipped with a New Process 208 Transfer Case.

 

[Tibby]

It can be done. Boyce Equipment did one for me years ago. It does take adapters, I think. I bought it from them and they did the swap, so I never saw it in the original. A good transmission shop should be able to do it. There is a need to have a switch on the passenger side of the transmission supplied with 12v. Mine has an NP208. All you need to do is go to a dealer to get the right speedo drive gear, assuming you are running a factory tire size and axle ratio. I found that 4.10 axles, a 700R4 with OE size tires is a driveable combination. Don't get an early model 700R4, they had issues which were corrected in later model years. I wish I was more mechanically savvy than I am.

 

[tanhmmwv]

I am in the process of restoring an 87 HMMWV and I did buy/install a 700R4 behind a 6.5 gm diesel. I painted the body,doors,hood and tailgate this weekend. Will be putting the body on in the next 2 weeks and hopefully finish ina month. Will let you know how it works.

 

[m38inmaine]

Advanced adapters makes a conversion kit for the 700R4/NP205 conversion, $495.