M1008 Driveshaft Length Please

[m38inmaine]

Will be picking up my M1008 in VA soon and want to make sure the replacement shaft I have is the correct length. Would someone please measure the rear shaft length main body center to center of the caps and post the measurement? 800 miles + from home is not a good time to discover you brought the wrong part! Thanks.

 

[CCATLETT1984]

it is the standard length for a K30 chevy, but I'm sure someone will be able to get the length for you. Remember to take new ujoints as well, and check the fluids in the drivetrain before moving it.

 

[aboonski]

Rear Driveshaft Measurement

If you will be taking a 54 1/4" driveshaft with you, measured from the center of the U-joint to the center of the U-joint or 56" at the longest point end to end you should be okay. I took both measurements to be sure that one of them would provide the accuracy you are looking for. I recently acquired a residue M1008 and the driveshaft was sitting in the bed of the truck - very rusty with frozen U-joints (probably due to the elements). I hope this will do you some good.

 

[m38inmaine]

Thank you for the measurement, I will campare it tonight to make sure. This one came from a standard K30 with a NP208 so it should be the same.

 

[aboonski]

Good luck on your trip!

 

[m38inmaine]

I measured mine at 51" form cap center to center. Perhaps your driveshaft came from a truck equipped with a NP205 transfer as used in other models of the CUCV which uses the longer shaft. I would like to confirm with someone with a stock M1008 to measure theirs to make sure.

Thanks

 

[aboonski]

Driveshaft Length

Actually I have two (2) driveshafts, both 56" at their longest length from the end of the U-Joint cap holder to the other end of the U-joint cap holder. I just crawled under my M1008A1 and that's what is in the truck for sure. The transfer case is made of aluminum so I guess that makes it a 208? I was told that the cast iron transfer case is the 205 model. I would hope that one or more other members will crawl under their trucks to take measurements of their shafts to compare with what I have. I have no reason to believe that my truck is anything but stock as far as the drive train is concerned. The other driveshaft was in the bed of an M1008A1 that I just got and it is identical to the one in my daily driver.

 

[Bozor1000]

RE: Driveshaft Length

The 205 is cast iron and the 208 is aluminum. THe 205 is gear driven, the 208 is chain driven.

 

[aboonski]

RE: Driveshaft Length

Thanks for the info about the transfer cases. I have one 205 transfer case sitting in an old 79 K5 in my back yard which is supposed to be pretty popular with the off-road and mud truck crowd. I think they used the 208 case in a lot of the full-size Blazers because I have another K5 that looks as though it has the identical transfer case as the one in my M1008A1.

I hope that Mark can get additional input from other M1008 owners so he can determine the correct driveshaft to use for his application. Sounds like the one he has will be 3" shy of the right size but it may still work if he doesn't go on too many bad roads with deep potholes, etc.

 

[Bozor1000]

RE: Driveshaft Length

The 79 may have a 203 in it. The both are cast. the 205 and the 203.

 

[aboonski]

RE: Driveshaft Length

I'll check it out! I guess there's a tag on the thing somewhere to indicate the variety.

 

[m38inmaine]

I remembered the local forestry station had a M1008 in the yard so I stopped by there today and measured theirs, it was 54" from cap center to center. The one I have appears to be too short and I will have to find the correct length one still.

Mark

 

[aboonski]

I knew it! I don't know where I got the extra 1/4" but you are definitely in the right ball park now. I always measure my driveshafts at their longest point because it is easier to hook one end of the tape measure on the end of the shaft and then pull it out to the other end. If you are under the truck, it is really hard to measure from the center of the U-joint to the other center if you know what I mean!

I also checked the transfer case in my 79 K5 and it is a 205 for sure. Looks like all of the others that I have in my other K5s and M1008s are all 208 models.

 

[Elwenil]

Center of the U-joint is the standard way to measure a driveshaft. This is how the manufacturers do it, and this is how driveshaft builders do it. In my experience with various trucks, a NP205 is longer than a NP208 so the NP205 shaft would normally be shorter unless the NP208 uses a slip yoke or is mated to a overdrive trans and the NP205 is not.

I was of the mind that the CUCV pickups came with a 205, but I read in a few places they came with a 208?!? I assumed with a 14 bolt and D60 axles they would have a comparable transfer case, if not that's sort of pathetic isn't it?

 

[CCATLETT1984]

all cucv's except for the m1028's and m1031's got the np208 (less parts in the supply chain)