Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[nomadsz]

Fitted the new DOuble ended, double UJ prop yesterday with some help form the Jeep Specialist MDG motors over in Portsmouth. They have re-opened and are going great gun. Lewis has 20 years experience on Jeeps at a dealer so he can diagnose pretty much everything.

HOwever on the drive back the new front prop was vibrating like an aggravated bee over 50mph and only calmed down over 70.
I currently have the extending end towards the front diff should i swap it round?

Seriously thinking of getting front prop made with a high angle CV joint made for the transfer case end and UJ at the diff end.

Is the vibration worse as the WJ is a UNIbody?? and does it need the CV joints to keep the vibration down??

[Cockney Boy]

Fitting them is not rocket science but if the Prop has had a major rebuild it will need rebalancing. Swapping the prop around will not do any good and the expansion joint needs to be at the front.

Get it professionally balanced and report back

[wildwood]

Also yoke on diff has to be same angle as prop to avoid the vibes.

[bigjeepzj]

  what they sed

[nomadsz]

Also yoke on diff has to be same angle as prop to avoid the vibes.

Yep the prop is full balanced it came form Bob grey thunder, before he upgraded to the dana 44 on the front, didn't know i had to rotate the diff i will give that a try. I though the idea of the DOuble double was so you didn't have to do that. Ahh well you live and learn.

[wildwood]

The angle between the front transfer case yoke and the prop can be whatever you want .......within the angles allowed by the joint of course.......that dynamic is sorted by the double cardon joint.

But as said above the diff yoke and prop should be same angle........anorak US advise is that they should be 1 or 2 degrees out......to accommodate things when you get your foot in the carpet and the diff wants to rotate to 0 degrees under load......... But maybe this is taking OCD to the limit

[donk498]

But if you change the pinion angle you may mess up the caster angle..........

[nomadsz]

 

But if you change the pinion angle you may mess up the caster angle..........

That was my thought as well can you fix the castor angle if you rotate the diff yoke up?

Currently get the whole car wheel alignment done!

[donk498]

Rotate the tubes in the pumpkin. Although not the quick easy fix you hoped for.

[wildwood]

  No easy way with the front.........gets very spendy ......just ask Bulldog

[nomadsz]

pics of the prop angle on the diff.

[donk498]

What joint do you have at the transfer end, uj or double cardon?

[nomadsz]

What joint do you have at the transfer end, uj or double cardon?

Double Cardon

[Cockney Boy]

The double should be at the TC end

[bgbazz]

That angle looks fine to me..but here's something to try..disconnect that front joint and rotate it 180 degrees, then re-connect..not suggesting it will work, but it did for me once in the past and I have no idea why.

[donk498]

So its a double cardon at both ends. In my mind that should be fine. I'm sure someone will correct me if I'm wrong. I take it the joints are in time on the splines?

[bgbazz]

Failing all of the above good advice, can't you just go back and explain the problem?

[Cockney Boy]

Is there any slop in the slide joint? You mention that it vibrates at around 50 but goes the faster you go. My money is still on balancing. Also that expansion joint looks over extended compared to other prop shafts ice seen. That might have something to do with the vibration

[JamesH]

I agree with CB and the 180 turn might help

Sent from my MZ604 using Tapatalk HD

[nomadsz]

The double should be at the TC end

There is one on each end

[nomadsz]

Is there any slop in the slide joint? You mention that it vibrates at around 50 but goes the faster you go. My money is still on balancing. Also that expansion joint looks over extended compared to other prop shafts ice seen. That might have something to do with the vibration

JUst been under there is some slop to be felt now in the joint, i can move it from side to side, after driving 260miles in the past two days and i do think i need a longer prop and less extension, i wil try the 180  flip but i think this one may need to come off. ANd i need a longer prop made up.

[donk498]

Just get that ones sliding joint extended.

[Cockney Boy]

Is there any slop in the slide joint? You mention that it vibrates at around 50 but goes the faster you go. My money is still on balancing. Also that expansion joint looks over extended compared to other prop shafts ice seen. That might have something to do with the vibration

JUst been under there is some slop to be felt now in the joint, i can move it from side to side, after driving 260miles in the past two days and i do think i need a longer prop and less extension, i wil try the 180  flip but i think this one may need to come off. ANd i need a longer prop made up.

I think you have your answer, any slop will creat loads of vibration you only need 10mm of slop to give you a harsh ride. I would like to know what that prop should fit as it clearly wasn't designed for your truck

[donk498]

Rich that prop was built for a wj. Grey thunder had it built, pay attention 

[nomadsz]

Just get that ones sliding joint extended.

where can i get that done at a reasonable cost