Driveline Angle Help Needed.

[JonnyBlazeLQ4]

I have an 85 C1500 that I had an axle flip done on and I ls swapped it this winter and my dyno tuner wanted me to have my driveline angles verified before he does wot runs. So I took it to a shop today and they said my angles were off 7 degrees and that my rear diff needs to come down and my trans needs to go up. I thought the axle flip kit had adjustments built into it automatically to keep it in place? Also, what do I need to bring my rear diff down? I used the Switch Suspension Squarebody Syndicate kit.

 

[Big Chip]

I used a Switch rear kit on mine and still needed to come down a couple degrees. I think they just get close on those angles and hope it works. Shimming the trans up a little shouldn't be too big a deal.

 

[PrairieDrifter]

ORD sells pinion angle shims, and I'm sure other places. They bolt to your leaf pack, like the rest of the springs and change your pinion angle as they have an angle cut. I think spec is within 3 degrees.
I wouldn't want to touch the trans if I didn't have to.

 

[TPISly-C10]

first do you feel any vibration in high speed? then angle got to be parallele but equal so if you have 6 up at the diff and 6 down on the trans that will be ok. i shim a bit my trans on mine and now running 4 link in rear i ajust it to fit

 

[CalSgt]

Without knowing anything about you lowering kit, if it has a lowering block they are usually tapered to adjust pinion angle. If its backwards it would throw the angle way out. You may need to find an axle shim or cut the perches off & weld on new ones set to the proper angle.

Ideally your trans tail shaft and pinion should be parallel, if the output shaft is 3 degrees down then the pinion flange/yoke should 3 degrees up. Some add a degree in at the pinion for axle wrap under acceleration.

For the trans mount adjustment your carb mounting location on the intake manifold should be level or close to it.

You might need compromise a little between driveline angle and carb angle unless you are able to fab stuff to make it perfect.

Get a cheap magnetic angle finder & start making adjustments. Since I have a lift and different trans & TC I had to make a spacer for the trans mount and use a few 1/4" thick washers to get it close.

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