taking care of the infamous 3" grinding

[oldscratchggf]

I`ve got a RoverTym 3" lift on my truck, and naturally, it grinds. I searched the boards a little bit, but did not come up with what I am looking for. My u joints at this point are pretty beat, so I was thinking of just replacing the whole driveline. Any other options, other than Safari Gard, for drivelines? I am interested in the SG because they theoretically get rid of the grinding, but I am not too keen on spending $1000. Any ideas?
-Nathaniel

[Mike Hippert]

Figure out the problem first! No need to spend $1k on something that may not be the problem!

Remove one driveshaft at a time and drive in diff lock to figure out where your problem is. I road on stock driveshafts for over a year (front is still stock) without many problems other then wearing through rear ujoints every 6 months. I had a rear DS made up for about $300 that allows for 30* of Ujoint travel (compaired to 15* for stcok) and I haven't had many p\roblems.

One thing I think most don't consider is the cost to maintain those high dollar DC shafts if they need replacment from getting muddy.

[oldscratchggf]

both the front and rear u joints are pretty ground up, so as far as I am concerned, really, it is just a matter of what I should do to replace them and get rid of the grind. Having them made with 30 degrees of travel took care of the grind?

[Mike Hippert]

UJs are cheap, I would rreplace them first. If they don't last very long then a DS may not be your only problem. How does the Pinion look incompairison to the T-case?

[Broke It]

Looking at the pinion angle in relation to the T-case is important. The U-joints need to be running at the same angle, this will cancel out vibration. The greater the angle on the U-joints the faster they wear out. I ran a CV drive shaft that was 12 inches long on my Jeep Rubicon, it had 34'degrees of possible angle and zero vibration. They cost about 300 for a new one. The good news is that the drivelines on a 90 are a lot longer and you will be able to use a larger CV-joint. I went through 3 of them because off over flex. Look at Tom woods Drivelanes on the web, the first 2 I broke he replaced under waranty even after I told him it was my fault they broke. When setting up for a CV-driveline the pinion need to be at 0'degrees in relation to the U-Joint and the CV takes all of the angle.

[Bowtracer]

Repace the ujs. Then do as mike suggested. Remove a shaft & see if the vibs change. I would start with the front first. I am not sure if this matters but replace the shaft in the same orientation as removed.
Then take a look at pinion angles. This has some effect on dl vibes. To get your pinion in line with the tc output will increase the angle on the shaft. There is a sweet spot someware?
This wil probly not cure the problem but will help. A couple of washers added to your rad arms & rear link is how that is done. If you are still on stock arms you might run outa threads so good luck. I just bought a gbr front shaft & that took care of mine. IMOHO that the gbr shaft rocks. My 110 is as smooth as silk.

[Mike Hippert]

If you are up for some reading check this out, allot of good info here

http://www.pirate4x4.com/tech/billavista/PR-shaft/index.html

[mikeslandrover]

What about a double UJ joint same as on the front of a discovery series 2? I thnk having a double UJ works the same as a CV joint :confused

[Bowtracer]

Its called a double cardin joint. A D2 front shaft will work but the uj's have no zirk. & to find gkn uj's that are greasable will be hard & $ IMO. You will also have to buy a flange for the output shaft for the tc to mate the ds. well you get it!!!

[mikeslandrover]

Its called a double cardin joint. A D2 front shaft will work but the uj's have no zirk. & to find gkn uj's that are greasable will be hard & $ IMO. You will also have to buy a flange for the output shaft for the tc to mate the ds. well you get it!!!
I've wondered about building a double cardin joint by using two UJ yokes and shortening a prop to suit :cool:

[rover4x4]

http://www.d-90.com/tech/cv1.html

[mikeslandrover]

Way to go :) :cool:
That is one useful page.
Do you think it would work with two UJ flanges( the bit that attaches to the diff bolted/welded back to back?

[oldscratchggf]

I appreciate all the responses. It definately looks like i`ll have to set aside next weekend to check it out. I`ll probably be back with more questions about it

[Bowtracer]

Gkn will have all the stuff you need in the UK>

[mikeslandrover]

I'm trying to avoid spending money :)