Thanks. Guess I wont worry too much about it either then. I did lighten the bed up a bit when I got it. I pulled the spare off, carrier off, put on the roll pan etc..

 

Just to throw this in there, on heavy trucks (semis, dump trucks, etc) You are correct on pinion offset. The offset needs to match the offset of the transmission, or you will get harmonic vibrations while under load. But thats w/ a stock suspension. With as much lift as you have, that would be way too much offset for a stock ujoint to handle reliably.

 

Cool. Thanks Blue rebel. If I have vibraions at higways speeds how will I know how much and which way to shim it?

 

I dont know for sure, I dont know anything about lifted truck driveline geometry, all my experiance is w/ stock. and then its pretty simple, ya just gotta match it

 

Looks like the two block is right on, I had my measurements right I also scored these fender flares for 20 bucks at the yard, Think i'll try em out for a while.

 

From my basic understanding of drivetrains in CARS, I would imagine that the more parallel that you can get your pinion angle to the output of the transmission, the better off you are. however when it comes to lifting a truck, the output of the transmission is much higher, therefore the more you can get your pinion angle to point upwards, the better off you are. In the pics you posted, your pinion angle looks almost perfectly inline with your driveshaft, which is fine. That's gonna save you a lot of time in changing U-joints.

 

Driveline geometry is driveline geometry. It doesn't matter if the rig is lifted or stock, car or truck. Ideally you want the pinion angle the same as the output on the back of the transmission/transfer case when you have a one piece driveline with only one u-joint on either end. When you start getting more lift the Band-Aid is to angle the pinion up because the pinion joint is the most likely to break and this alleviates some of the stress from it making it live a little longer. It does put the two joints slightly out of phase but here you're looking at the better of two evils.

Probably the best fix is to do a double cardon joint at the rear which changes the geometry as it has 2 joints right next to each other and alleviates the angle by splitting it between the two.

Also you don't want the joint perfectly straight either as it will only every wear on a couple of the needle bearings in the joint and wear it out sooner.

I am curious how you are liking your shackle flip kit. I'm thinking about doing this myself and deleting the blocks all together. I was a bit worried about the pinion angle and from what you're describing it sounds like I will have to address it.

 

Ditto. I want one of these fro my bronco