Desparodo

I had 2 inch lowering shackles on an 2006 F 150 with the 2 degree shims for pinion angle. My question is with the new shackles I have would the old shims be correct for the pinion angle. The service manager at the dealership said I probably wouldn't need them but I feel like the angle should be put back to keep down any vibration and excess wear. Thanks for any help and opinions.

rojizostang

Perhaps you can get a pinion angle measurement before the installation, and then one afterwards to determine how much the angle has changed. If there's no drive line vibration after the install then the shims could be left out. If there's a vibration afterwards, then you'll have an idea of how far the angle needs to be adjusted to retain the original setting.

I guess if you're really good at geometry you could figure out what size shims you need from the difference in the angles, but it would probably require some trial and error to return the pinion angle to a stock or near stock setting.

I think I would just try the 2" shackles and not worry about the shims until it's confirmed they're needed.

riptide88

Can you post the specs of your truck and pics when done?
are you removing the rear blocks too?
let me know what kit you got and if you had to cut the frame too please

Ive got an 18 4x4 and removed the blocks and its about 1-1/2" high in the rear still so im thinking its time for some shackles.

Fly50

Subscribed
I've been wondering if i could remove the blocks and still use the stock U-bolts?
I was also going to do the drop shackles and was also wondering about the shims too.
I'm between 2 1/4" - 2 1/2" raked stock, looking to get it even.
The blocks are 1 1/4" so id be looking for a 1" drop from the shackles.