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DonImbimbo
08-08-2023, 07:43 AM
I recently got my wheels and tires, which allowed me to install the engine and trans.

188461

I also got my replacement driveshaft. But putting things all together the pinion angle looked out of wack. So I removed the driveshaft and did some measuring.

I set the rear springs so that the ground clearance at the rear of the cab was the same as under the firewall, approx. 7 inches to the floor.

Using my digital angle gauge, I zeroed it on the front of the crank pulley. I checked on the face of the transmission shaft and it was within 0.2 degrees (should have been zero).

I then checked the face of the rear pinion and got 2 degrees, pointing up.

I previously added 3/8 inch spacers under the transmission mount to help center the tail in the drive shaft tunnel. Removing the extra spacers I think will only correct the angle by 0.6 degrees or so.

I double checked my rear control arm settings, per the build manual.

It's looking to me as though the upper control arm wants to be shorter, but there is only 1/4 inch of space left on the threads.

I realize that the pinion angle really needs to be done with the suspension fully loaded But even then if the frame is level to the ground it would only affect the driveshaft angle and not so much the pinion angle. Correct?

Any thoughts or ideas?

DonImbimbo
08-14-2023, 06:55 AM
Resolution, for now....

I shortened the rear upper link as far as it will go and now get 0.5 - 0.6 degrees of nose up on the rear compared to the trans. It looks like I would need to take 1/8 to 1/4 off the end of the upper link to get closer to perfect. But I'm going to leave things the way they are until I get further along with the build.

mkassab
08-14-2023, 03:37 PM
Resolution, for now....

I shortened the rear upper link as far as it will go and now get 0.5 - 0.6 degrees of nose up on the rear compared to the trans. It looks like I would need to take 1/8 to 1/4 off the end of the upper link to get closer to perfect. But I'm going to leave things the way they are until I get further along with the build.

Don, as long as you're withing 1* difference between the Crank/Trans output shaft and the rear end you're good to go.

Mark