Deleting Rear Block and Drivetrain Vibrations

Viking · Jul 4, 2012

My first super duty was a E99 v10, build date 12/97. It did not come with rear blocks and my TC bolts worked themselves out eventually. I have read about the vibration problems that Ford could not figure out. I am wanting to level my truck now by deleting the rear block but have stopped due to my previous problem.

I don't understand why there is a vibration problem if the angle gets closer to level.

Anyone wanna fill me in on why and how?

TARM · Jul 4, 2012

They are there to reduce frame vibrations. A number of vehicles have them. Its a vibration dampener. The thing is every vehicle is a bit different so you may take it off and have no issues or start to feel from light to heavy vibration. I say take it off and see if you notice the change. I know a ton of people have taken them off when doing the exhaust and have not noticed any negative issues. Of course this does not mean there were not any. But from what I understood it was for occupants not to prevent the vehicle from coming apart. I would think some red or purple loctite would do the trick to prevent bolts from coming out.

TARM · Jul 4, 2012

They are there to reduce frame vibrations. A number of vehicles have them. Its a vibration dampener. The thing is every vehicle is a bit different so you may take it off and have no issues or start to feel from light to heavy vibration. I say take it off and see if you notice the change. I know a ton of people have taken them off when doing the exhaust and have not noticed any negative issues. Of course this does not mean there were not any. But from what I understood it was for occupants not to prevent the vehicle from coming apart. I would think some red or purple loctite would do the trick to prevent bolts from coming out.

Viking · Jul 4, 2012

Well I guess just go for it and see what happens always works haha.

TARM · Jul 4, 2012

That is what I would do. At worst you put it back on.

I still wonder how the vibration dampener really is effective given the way our truck bodies are secured to the frame and then the addition of varying loads and their placement. All than and some 25lb weight hanging off a cross member is going to do something substantial is just hard to swallow but in many times its amazing the effects small changes in the right spot.

Viking · Jul 5, 2012

I havce emailed airbagit it to see if they have any input on this.

TARM · Jul 5, 2012

Let me know what you hear. Maybe it will be interesting.

DocBar · Jul 5, 2012

I removed my stock rear blocks and replaced them with the block provided by Newton when I added traction bars. I now have a slight vibration. The Newton block is about 3/4" thicker than stock. I wouldn't think that would be enough to change the angles enough to cause any issues.

TARM · Jul 5, 2012

Hang on are we talking about the blocks between leaf spring and axle or the one big iron block that a number of trucks and cars having hanging down right at the end of the transmission? I must have been real tired last night as reading it now I see it looks like you are speaking of the spring blocks. LOL But the answer I think will still be about the same. Its hit or miss on how it effect vibrations. Some trucks get it bad others nothing. If it is an issue you can pick up some shims to get the pinion angle back to what it was.

Viking · Jul 5, 2012

TARM said:
Hang on are we talking about the blocks between leaf spring and axle or the one big iron block that a number of trucks and cars having hanging down right at the end of the transmission? I must have been real tired last night as reading it now I see it looks like you are speaking of the spring blocks. LOL But the answer I think will still be about the same. Its hit or miss on how it effect vibrations. Some trucks get it bad others nothing. If it is an issue you can pick up some shims to get the pinion angle back to what it was.

I didn't know where you were going with the vibration dampener haha

NotStock · Jul 5, 2012

You should be ok with removing your rear block and not getting any vibrations. Normally you will get vibrations when a ujoint is perfectly straight. They want to see a little bit of angle to prevent them from vibrating. You will want the angle to be down some so that under heavy acceleration the pinion rises up and the angles straighten out some. If you take the block out and do get a little shutter, you can get whats called a pinion shim. Its a small wedge shaped aluminum piece that will go between the axle and the spring pack. One thing to check for is that you have enough threads on your ubolts to take out the block. If you dont and need some custom ubolts made up, shoot me a pm. We can make any size you need in house.

Viking · Jul 5, 2012

NotStock said:
You should be ok with removing your rear block and not getting any vibrations. Normally you will get vibrations when a ujoint is perfectly straight. They want to see a little bit of angle to prevent them from vibrating. You will want the angle to be down some so that under heavy acceleration the pinion rises up and the angles straighten out some. If you take the block out and do get a little shutter, you can get whats called a pinion shim. Its a small wedge shaped aluminum piece that will go between the axle and the spring pack. One thing to check for is that you have enough threads on your ubolts to take out the block. If you dont and need some custom ubolts made up, shoot me a pm. We can make any size you need in house.

Thanks but I am heading out to the bigger city to pick up some u bolts. I got a place to grab them, they make them on the spot for like 20 bucks. I also ams still waiting to here from airbagit on the inquiry about shims.

Thanks!