Decided to check my pinion angle for the first time ever. I can't believe I haven't looked in to getting suspension work for the rear until now. I guess with the truck being lowered 4" in the back and over 550 passes at the drag strip the leaf springs have been through hell. My pinion angle is at +5 just sitting in the driveway. I'd imagine that goes to +10 whenever I lay into it. Could be the cause of the slight vibration I feel around 90mph at wot. I'll be ordering caltrac bars very soon and also need to shim my rearend to about -5 I guess. Feel free to put in your .02

Where do you get the rearend shims from?

 

you did measure on a flat surface right? just curious because there isnt any level driveways around my side of town.

 

Check Summit Racing or StylinConcepts

 

you also dont want your rear end sitting at a perfect 0 unless your in a 4 linked drag car. you want it around -2 through -5* of pinion angle. i have some custom -7* shims around here somewhere that i could sell if i can find them. that should set you right back into the -2* range of pinion angle if your measurements are correct....and in theory haha.

 

i'm looking into the pinion angle too. i get vibration past 100 and we measured (not sure right) and it was like -6 and -6...

 

I found 4wheelparts to be the cheapest with shims, have fun it took 3-4 tries to get rid of my vibration.

 

I run -3 and with the Cal-Tracs backed off a 1/2 turn running 1.59 60'. I got my shims from Summit.

 

how do you measure pinion angle? i think mine is ok right now but it wont be if i take off my shackles and hangers for a flip kit

 

once you figure out what angle you need, do yourself a favor and look up JKW Offroad to get you some good shims. They make all steel shims of any angle that actually bolt to the spring pack. I've used them on several projects.

 

My truck was not on a level driveway when I measured. I took that into consideration. I checked the angle on driveshaft and rearend and subtracted the difference. Maybe that's not right... hmm. Is it? I'll recheck it on level driveway to be sure.