axle swap question (1 Viewer)

[njshofear]

Will a 78-79 front axle bolt up to the driveshaft from a 75? IM thinking of just swapping in a 78-79 axle to have fine spline outers and disk brakes...is this gonna be as easy as i think it will, or is it gonna be a PIA? I can allways use my stock 3rd member if that would be easier i suppose. I searched but couldnt seem to find what i wanted.

My biggest worry is the driveshaft not bolting up. Are they the same or different?

 

[splib]

I think '74 to '84 front drive shafts are the same.

 

[Thornton]

Looking at SOR's catalog splib is right. I did a '78 front end in my '71 and also installed the 4spd and t-case and drive shafts out of a '78. the issue I had was the flange on the rear did not match. I ordered a new flange from SOR that was course spline for the '71 rear and set up to accept either bolt pattern for the drive shaft. Worst case is you may have to get a different flange.

 

[FJ40Jim]

Driveshaft will bolt up.

Issues include:
-Brake line drop is on other side of truck. Fix is to install 75 hard lines on 76-later axle, or run 1976-later style hardline over to the pass frame rail and drop the line to the axle over there.

-79-later frt axle will have 3.70 gears, instead of current 4.11. The rear diff could be swapped at the same time to get 3.70 all around for improved street driving, or the front diff can stay w/ the truck (thereby avoiding any d-shaft issues) and just plug the old diff into the new axle housing to get the finespline, big knuckle outers.

 

[njshofear]

Ive been told the axle has 4.11 gears, good to know about the brake lines, ill have to deal with that.

Driveshaft will bolt up.

Issues include:
-Brake line drop is on other side of truck. Fix is to install 75 hard lines on 76-later axle, or run 1976-later style hardline over to the pass frame rail and drop the line to the axle over there.

-79-later frt axle will have 3.70 gears, instead of current 4.11. The rear diff could be swapped at the same time to get 3.70 all around for improved street driving, or the front diff can stay w/ the truck (thereby avoiding any d-shaft issues) and just plug the old diff into the new axle housing to get the finespline, big knuckle outers.

 

[rsc71]

you can look at this web page to see the different bolt patterns
Cruiser Outfitters