Just picked up a 1991 Dakota V6, manual tranny 2wd truck. Previous owners replaced the rear axle with one from a 4x4 Dakota suposedly a 91 also. The original differential blew up. The axle under the truck now bolts under the rear springs while they said the axle they took out originally bolted on top of the springs. The rear of the truck sits really high now. The driveshaft also looks like it's at a steep angle. Can I cut the spring mounts off the top of the axle shafts and reweld them on the bottom? Did they use some axles on top of the springs and some underneath?

 

Would not recommend cutting brackets and rewelding on other side. It will lower the strength of the axle. You could try removing or changing the leaf springs to lower the rear end to match the front.

 

That was the other thought I had. Are the leaf spring mounts the same on the 2wd and 4wd trucks? Are the springs different?

 

As long as it is first gen, they should mount the same with the exception of 4x4 goes over axle and 2x4 goes under. Also, 4x4 model may have more leafs in it than the 2x4.

 

You can leave the spring perches on the top. Buy two new ones from summit or somethin and weld them on the bottom, putting the axle back on top of the leaf springs. That is how its supposed to be for a 2wd. This wont weaken it to worry about it. People with 700 HP+ race cars weld to thier axle housings all the time. You dont need to worry about strength. You need to worry about setting the pinon angle corectly.

 

You can fix the angle of the pinion just by putting a pitch wedge in the leafs. As for weakening the axle and not worrying, I don't believe that is a response that should be given. That's like saying go ahead and cut the mounts off the axle and reweld them on the other side because it doesn't matter. There are several things that a pitched angle on the truck can do that is not good for a vehicle. Short cutting something or ignoring it to fix it isn't the solution.

 

I stopped by a used parts salvage yard today and he said the 2wd and 4wd used the same springs. he said he had a 2wd axle but wouldn't take my 4wd axle in on trade cause he didn't know where it came from, lol. I guess I'll go with welding some mounts on the bottom of the axle and moving the axle above the springs. The guy I got the truck from said he still has the 2wd axle so and I can have it if I get down to pick it up, about 55 miles away. Maybe I can put the inards of the 4wd axle into the 2wd then put it back on and be good to go?? Will the differentials swap? He said the idler gears broke out of the 2wd axle that's why it was changed out.

 

They should swap out as long as they are the same size axle. i.e. 8.5, 9.0, 9.25, 9.5 etc....
Would recommend a pro do the work for you though unless you have done it before. Don't align gears and pinion right you'll end up with a whine and have to do it all over again.

 

If you use a pinion angle finder, you can weld the perches on in the correct spot. It is important to get the distance left and right correct, and you need to make sure the axle is perpendiculat to the frame. The baest way to do this is set the new spring perches on your leaf springs. Set the axle on top of the perches. Measure to make sure the axle is centered left to right and forward to back. Use a pinion angle finder to set the angle the yolk points toward the driveshaft, then tack weld the perches on. Pull the axle out and finish welding on the perches.

 

I might be in luck. The guy I bought it from dropped off the original axle today. The differential carrier looked ok to me. The idler gears were gone and the hardened pin they ride on was broken. I think if I get a pair of gears and a new pin I can fix it and put the original axle under the truck. Anyone know of good places to get those parts? Preferably cheaper if possible.