hmmwv15

I was trying to figure out if the skid plate for the gas tank on the 2wd would fit on the 4wd, (it will with mods) and noticed that the driveshaft on the 2wd was 2-3 times bigger than the one on the 4wd. (these trucks are 86 and 87 models) Does anyone have any idea why?

the_gunslinger

steel vs. aluminum?

hmmwv15

No idea. Both are stock and haven't been replaced (to my knowledge)

Do you think the 4wd's could be solid, but the 2wd's hollow??

the_gunslinger

could you get some pics? i'm a little curious myself, now...

89macrunner

what do you mean by bigger? bigger as in longer? or thicker?

it would be longer because the theres no transfer case. if its thicker than i dunno

Zealot

I am pretty sure he means larger diameter. One possibility is that there is a longer distance between point "A" and point "B", so there is more strain on the driveshaft, thus having to be larger.

stormin94

Skid plate will probably work. May require some drilling/ cutting for size, but it'll probably work. As for the shaft, I dunno. Is one a V-6 and the other a 4???

CanTheWhales

I didn't know the 4x2's even had gas tank skid-plates; learn something everyday I guess...

hmmwv15

Forgot to check this thread! Yeah it's bigger in diameter on the 2wd. Both have same engine, and it might be what Zealot was saying. I'll take pics tomorrow.

dijlop

hmmm. maybe you shoulda kept the 2wd truck as your main ride huh? traitor... hehehe

Travisfab

I picked up my 2wd driveshaft today and was surprised by how light it was.

hmmwv15

Didn't really have a choice, it just died on me so I needed something else.....




And yes I am a traitor..

hmmwv15

Well they look the same from the pictures, but there is a difference. I'll measure the diameter tomorrow.
Anyway, here they are: (2wd is first)

drew303

probably just bigger because its longer.

MudHippy

O.k., from what I see there I can tell you that they are both 4 cyl driveshafts. One is a 7.5" diff, and the other an 8". I have seen a 4 cyl 2wd driveshaft that was a little thicker (and longer) than a 4 cyl 4wd driveshaft. The Turbo/V6 driveshafts are quite a bit thicker/wider(same wall thickness tube though)even than both and have incompatible bolt patterns. All use interchangeable parts(u-joints/slip yokes), meaning you can mix & match parts between all 2wd/4wd 4cyl/V6 shafts, to make them fit where needed(some cutting and welding is required to swap slip yokes, obviously). The only difference there is the 4wd u-joint yokes have longer mating stubs that extend deeper into the shaft for added strength. Some u-joints may have different part #'s depending on application, but all fit in place of the other, possibly minor strength differences also. All this is what I have found to be true of 86-95s anyway.

hmmwv15

Both are carbed 22rs. If that helps.....

Zealot

Mudhippy are you saying that a driveshaft out of a 3.0 is thicker than a 22re? If they are, are they interchangeable? It would be pretty cool to swap for a stronger driveshaft.

MudHippy

Well, I only know the "how" on this one, not the "why". I would tend to think it would be related to the length of the shaft, weld-weld, for use behind the same engine.

MudHippy

Yeah, but the bolt pattern is different. So, you'd need to take the parts that bolt to the companion flanges at the differential and the transfer case off the 4 cyl shaft, and put them on the u-joints of the V6 shaft. So it will bolt up. Or leave it as is and get the companion flanges that the V6 shaft is bolted to and put them on your diff. and t-case. Either way.

Zealot

Cool, but is it worth time, effort, money to do so,.