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Hello All,
I was able to get my J40 springs on and cycled this weekend. So while the springs are all apart after cycling I always take a carbide cutter and open the center hole to a 1/2" in order to use 1/2" socket head Allen bolts. Anyway- I was wondering if you all might know off hand if there is a degree of shim commonly used with the J40 spring on the FSB?? Honestly moving the perches is best practice but a solid steel shim bolted to the leaf pack I have zero problem with-- and the shims are available here locally in Phoenix which is nice. Moving perches is just a total suck that I'd rather save for--- never.

** On a side note the Raptor that was in the 2010 Baja 1000-- the truck that ran the 100k something mileage Ecoboost-- that truck ran Deaver springs with (2) socket head Allen bolts for leaf spring pins. I've broken a couple of regular center pins in leafs but 1/2" grade 8 bolts seem to live quite nicely

Thanks for the help,
Matt

I want to say I used a 4 degree shim when I had my J40s but before the 9 inch.

Just gong to put it out there to what I found when using the J40 rear springs, removing the cast wedges, and running the 8.8 with stock spring perches you will need about a 16*-20* shims under the springs if you doing rotate the perches. I put a lone 6* shim in and it wasn't even remotely close.

Bump! Same situation here with camburg shackles. I cant find any info on the stock wedge degree nor what works shim wise with the J40's and 8.8. HELP!

Well I will tell you what I did- used the absolute lowest profile Spring pads you can find and put new on.

Pad as in new spring perch? It’s looking like that is the way to go. Do it right the first time.

I knew I was typing the wrong thing lol- get the perches- it’s a 2 hour overall per side deal at the worst. A buddy to help center and position is pretty handy. Get the lowest perches you can find as the J40 sit a bit too high.

Your drive shaft should be 2°-3° up of in-line with your pinion at ride height. Ideally it would be exactly in-line but you set it a little off so that the u-joint moves a little to keep itself lubricated. This is true for all double Cardan joint drivelines.

Thanks for the info! I plan on tossing in the factory wedges just to see if I get lucky but will be prepared for repositioning the spring perches to spec.

Ditching the wedges will make it worse-