Axle swap/ pinion angle

[DBear]

Hey guys...just got done swapping a gm14 bolt into my 71 K10 suburban. For suspension set-up I am using stock rear springs out of a mid 70's truck with an zero rate attached to the leaf pack. I am also using a 3 inch lift block from Rough Country to get a 4 inch lift total.

Here is my issue.....with it all bolted in, the pinion yoke is sitting about an -3 degrees angle, meaning the pinion yoke is pointing toward the ground 3 degrees. Also, the spring pads on the axle tubes are doing the same......and....the u-bolts are slanting forward (toward the front of vehicle) as well. This is turning into a small nightmare. Any suggestions?? They would be greatly appreciated.

[dieseldawg142]

are'nt your blocks tapered? most usually are. other than that, throw some shims under the leafs to turn your axle up. if you have access to a welder, you could move the spring pads...

[DBear]

Yes...The blocks are tapered. I have taller end toward the rear of the vehicle. Something just seems really odd about the whole set up. I really don't wanna mess with the spring perches though.

[DWilbur]

it sound like you may have the block upside down. the square side of the lift block should be touching the bottom of the leaf spring and the angled side of the block should mate up to the axel. longer side of the block to the rear.

[DBear]

pretty sure its not upside down.....because the pins wouldn't be lined up. I am going to check it, but it sure looks odd. Seems like not matter what the blocks do or the zero rate does, the spring perch should be level to the floor.????

[rogerapage]

Get an angle gage to measure the degree of the output shaft and the pinion. The measurement should be 0 to 3 degrees. Example (my truck) the transfer case was 3 degrees past 90 (87) from horizontal. The rear-end pinion was level to horizontal (0). It was in spec but still vibrated. I had a machine shop make angle shims to install on the spring perch to point the pinion up. I gain about 2 degrees up. The transfer case was down 3 degrees the pinion up 2 degrees. 3 minus 2 = 1 degree in spec.

[imjeff]

Can you post some pics?

[1malo68]

I swapped a 14 bolt into my 68 shortbed. I ended up doing the spring perches but everything you ever wanted to know about driveshaft angle can be found at here http://www.pirate4x4.com/tech/billav...aft/index.html
Hope it helps you.

[Mr. 250r]

Sounds like the blocks are in backwards if the lowest point of the block is towards the front of the truck and the highest point is at the rear the pinion should face as up as possible if its backwards it would point everything down or am i backwards... lol

[dieseldawg142]

Originally Posted by Mr. 250r

Sounds like the blocks are in backwards if the lowest point of the block is towards the front of the truck and the highest point is at the rear the pinion should face as up as possible if its backwards it would point everything down or am i backwards... lol

normally you are correct, but just to throw some confusion out there, here's the 3" blocks i mounted backwards in my k30 crew

why? 8" lift, lowered the t-case an inch & the carrier bearing an inch & a half to lessen driveline angles. forgot to compensate for the shackle flips, pinion was too high, spun the blocks around & been running them for yrs like this

[OLDCHEV4X4]

The yoke coming out of the transfer case, and the pinion coming out of the rear, should be at the same angle when using a stock style drive shaft. Buy or make angle shims to correct this.