lift, rear driveshaft?

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martyanderson10
Posts: 6
Joined: Sat May 04, 2013 6:19 pm
Location: TN

lift, rear driveshaft?

Postby martyanderson10 » Sat May 04, 2013 6:29 pm

I put 4" lift blocks on the rear of my 87 Bronco 2 today and when I was done the rear driveshaft was too short. I lengthened it the correct amount and it was better BUT the angle on the cv joints is so extreme that after about 5 miles the front cv joint on the driveshaft started making a hell of a racket and was so hot it was smoking. I know what the problem is, it has too sharp of an angle on it. The blocks have a small taper to them and they are on correct. How can I correct the angle of the driveshaft to get rid of this problem? Thanks for any help.

dgl6y6
Posts: 84
Joined: Wed Jul 22, 2009 8:56 am
Location: St. Louis

Re: lift, rear driveshaft?

Postby dgl6y6 » Mon May 06, 2013 7:14 am

You can grind the the spring and shock brackets off and weld them back on further forward to tilt the pinion angle. this is going to cause long-run problems like the gear oil not getting to the pinion bearings. I would replace the cv driveshaft with one with u-joints. idk what the centerpiece in a double cardan joint is called but ive seen them sold alone. you could add these on both ends of a stock ujoint based driveshaft. this would fix the angle and probably the length problem too.
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martyanderson10
Posts: 6
Joined: Sat May 04, 2013 6:19 pm
Location: TN

Re: lift, rear driveshaft?

Postby martyanderson10 » Fri May 10, 2013 5:28 pm

I did get a ujoint style driveshaft and I will have to shorten it since it came out of a manual trans but no big deal. I cut the lift blocks at more of an angle to rotate the differential up to decrease the angle. After seeing your comment about the pinion gears and lubrication I have some concerns. It tipped the differential up about 4". I will put as much lube as I can in the diff. case as well. Do you think this angle will cause any future problems? Thanks for your help.

dgl6y6
Posts: 84
Joined: Wed Jul 22, 2009 8:56 am
Location: St. Louis

Re: lift, rear driveshaft?

Postby dgl6y6 » Sun May 12, 2013 2:49 pm

I guess its possible you might notice some power loss from having more than normal amount of gear lube in the differential. I don't know if you can actually damage anything from being over fill though. The only other thing I can think of that might be a problem is bleeding the rear wheel cylinders since they will be an angle now the bleeder screw will not be on the top you may not be able to get air bubbles out. as for the drive shaft , when a u joint is bent at an extreme angle the rotation isn't exactly smooth. I had a drive shaft kink on me and it broke the output shaft on a transfer case. I would say as long as the yokes keep a reasonable amount of clearance from each other while rotating, your probably not in danger of kinking.


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