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Boonetown123
08/29/2014, 10:43 PM
My machanic friend adjusted my torsion bar by only 2 inches but I wanted the full 3 if not more. He said that's to up to specs and the torsion bars will break. Is this true??

Triathlete
08/30/2014, 09:11 AM
There are many on here who have their torsion bars cranked pretty much all the way and I have not heard of any breaking. If it is a concern though there are heavy duty torsion bars available through indy4x.

JoFotoz
08/30/2014, 09:22 AM
Ditto Billys thoughts...

Mine are cranked at least 3.5 inches on OEM T/bars...
...no T/bar issues...and I've never heard of one breaking either.

Maybe your mechanic is playing safe, liability wise?

You may / will however have issues with CV boots and CV joints..
...due to increased angle.

CV boots may well tear as they have become 'accustomed' to a straighter angle...
...fitting new ones will help, as they are supple and will conform.

Also added angle will stress your CV joints.

A diff drop is recommended to help with both of these issues.

Cheers

jo

Marlin
08/30/2014, 11:45 AM
Be warned, if you do the diff drop,the CV joints will thank you, but your prop shaft will not. I am on my third prop shaft, (the most recent one made it a few days before the boot tore). Prop shaft is easier to replace than the CV joint:) You can also have a custom prop shaft made, where as CV joints are limited to what you can find. Disadvantage to cranking the torsion bars, you lose your down travel and makes the ride worse. There needs to be a happy medium, Jo is running huge tires, and has to lift the front to squeeze the rubber in. I am running large tires and gutted the fenders to make room, so I managed to lower the front end down a bit from my original cranking, which improved performance.
I highly recommend the Indy4x torsion bars, they are pretty good.

JoFotoz
08/30/2014, 11:58 AM
I'm confused! ( easily done!)


Be warned, if you do the diff drop,the CV joints will thank you, but your prop shaft will not. I am on my third prop shaft, (the most recent one made it a few days before the boot tore). .

You are the first I've heard of having front drive shaft issues after lifting..
...maybe I missed other threads though.

Rear shaft..YES..with 35's it gets a tad short if you use adjustable rear links to center wheels.

And.. not sure what boots you speak of..
...I've never seen boots on the front drive shaft.... :_thinking

Jo

Marlin
08/30/2014, 12:45 PM
Take a look at the front prop shaft. It is a CV style shaft, has internal boots fore and aft. If you drop the front diff too much, it pinches the boots on the "cup" portion of the flange. The flange will deform to fit the new angle, the boot, not so much. The boot is not obvious like the CV joints, as they mount external to the shaft, the prop shaft is internal to the flange assemblies. Crawl under there and look
As for rear axle, I run the adjustable rear lowers, centered the axle and have been fortunate with no problems.
JoeD did my diff drop, CVs are perfectly straight (on a note, they do not like negative angles at all)

The arrow points to the boot location. The curve represents the changing angle as you lower the front differential. As you can see, there is not a whole lot of room for angle change. You may be driving around with ripped prop shaft boots right now. My last shaft boot ripped 3 or 4 years ago, but I never really had problems until I started playing in water and mud. So, if you stay out of mud and water, just add grease every so often, probably be fine. My last one started grinding, it was full of dirt. This new one got washed out in the pond in front of Baby Lion's back at Moab, so it is already making noise. Full of sand and grit.
http://www.vehicross.info/gallery/data/500/medium/prop_shaft.jpg

You learned something new today!! At this point, it doesn't happen too often with the VX!

JoFotoz
08/30/2014, 01:27 PM
Ah..OK

Its a difference of terminology..maybe my residual Brit speak!

I call that a "cuff"

Suffice to say..I've never had an issue..
...and your problems are the first I've heard of.

Jo

Boonetown123
08/30/2014, 09:30 PM
I appreciate the help you guys!

Marlin
08/30/2014, 09:59 PM
Not sure how many have dropped their diffs,but they may have the problem and not even know it. Unless you take a flashlight under there and look into the assembly, you would never know the rubber cuff is ripped, until water/dirt gets in there, which would not normally happen unless it was submerged, which would have to be a significant depth to reach that high.

Triathlete
08/31/2014, 08:19 AM
This is not so much a "dropped diff" issue...though that might accelerate the issue. Over time those boots deteriorate. The dirt/grime from offroading speed it up. My diff is not dropped but my prop shaft went. The front joint had about 1 inch of play in it. Replaced with a low mileage trooper unit (exactly the same) a little over a year ago.

Boonetown123
08/31/2014, 10:32 AM
Will doing the ball joint flip decrease the stress on the cv axle?

Triathlete
08/31/2014, 10:43 AM
No. Ball joint flip makes alignment easier after a lift.

Marlin
08/31/2014, 11:16 AM
Billy, the dropped diff certainly causes failure. The prop shaft was designed to always stay at a certain angle, not like the CV joints. As illustrated in the photo, there is not much room for angle change. Less than an 3/4" in play in either direction. The cuff was not meant to flex either. I would be curious for those with diff drops to crawl under the truck with a light and see how much metal deformation has occurred, and if their cuffs are ripped.(Only my front ones ripped) How many have actually installed diff drops? That would be a good survey:)

I do agree that even without the drop, the cuff can tear, but much the same as a CV, keep adding grease, stay out of mud and water, and it will probably last years. My wife has a torn CV boot, haven't had a reason to repair it, if the CV gets noisy, there are lots of troopers in the yard:rolleyes:

JoFotoz
08/31/2014, 11:23 AM
I've had the diff drop for about 5 years...


...and no cuff issues... YET!


Good to know though...
..and luckily I have a spare complete front shaft if I ever need it :thumbup:

jo

Marlin
08/31/2014, 11:30 AM
I've had the diff drop for about 5 years...


...and no cuff issues... YET!


Good to know though...
..and luckily I have a spare complete front shaft if I ever need it :thumbup:

jo

It depends on how much you dropped the diff. At the time, I was nose high in the air on the front end, and Joe did a decent drop, will need to measure to see how much. I would say an inch is probably fine, and does a world of good for the CVs, so well worth it IMO. I will not be repalcing the shaft again, I will have one of the shops fab a universal joint shaft to go in its place. Shouldn't be too expensive, hardest part will be keeping the original bolt pattern, or fabbing an adaptor to make it work.

JoFotoz
08/31/2014, 11:39 AM
Maybe...



It depends on how much you dropped the diff. At the time, I was nose high in the air on the front end,
and Joe did a decent drop, will need to measure to see how much. I would say an inch is probably fine,

Mines a T/bren drop...so 2.5 inches IIRC

Lets see what your poll results indicate.


Jo

JoFotoz
08/31/2014, 11:43 AM
Glad to help...:thumbup:


I appreciate the help you guys!

One other thing...

If you do go with a diff drop...you'll need to modify your cross member
by either cutting out and welding a strengthening plate, or putting drop
brackets on it too.

jo