05 Flame Red TJ Build

[Alex01]

What I'm asking is why don't you have it more even, like 12 and 12?

The atlas combined with the GR crossmeber raised my front ds angle. I could have lowered it by clocking the TC but I didn't want to increase the rear since I'd need to further raise the TC to clear the skid. As far as 9 vs 12 on the pinion I wanted to have some caster.

 

[JMT]

At 8.5 /8.5 it’s not bad and doesn’t come on till 70mph. Then it’s not droning bad and the oscillations are so faint it feels almost like one continuous vibration.
Is that just a balance issue?

 

[bobthetj03]

I'm hoping it is. If not, I Can't find a solution.

 

[JMT]

The atlas combined with the GR crossmeber raised my front ds angle. I could have lowered it by clocking the TC but I didn't want to increase the rear since I'd need to further raise the TC to clear the skid. As far as 9 vs 12 on the pinion I wanted to have some caster.

I remember the clocking discussion now. Strange to me the pinion and driveshaft angles can be so different and not have vibes. What am I not understanding? Is it something about the aftermarket driveshaft?

 

[JMT]

If it is the stock driveshaft push up and down on the slip joint to check for play. Mine did that terribly.

I DO have some play at the slip joint. It’s not bad, but I compared it to my Adam’s and there was no play there. Probably not supposed to have any play. That could be the problem.

I checked the u-joints and I don’t have any play there.

 

[Cross-Threaded-06TJ]

My last 2006 TJ Rubicon did the exact issue yours is having. I had the front shaft rebalanced and It fixed it that time. I only had a 2" OME lift though. This go around with my current 2006 I just went hubs kit due to how much lift I used.

It may be worth a try for a rebalance only.

 

[JMT]

Before spending a bunch of money, take that front DS to a driveline shop and have it checked. Did you dent it last trip out?

Might be a simple as a bad ujoint. Look in the caps. If they are dry or have any powder in them, replace it. You might have a bad centering ball or slip joint too. Lots can wear out in the front d/s

Exactly the advice I was looking for. Somehow I missed this post yesterday. Glad I went back to read everything through again. Thanks Mike.

 

[IPerkWVU]

They weren’t lying. The Jeep is telling me it needs BIGger tires

Yep, this is how it happens!

 

[JMT]

Did you dent it last trip out?

Might be a simple as a bad ujoint. Look in the caps. If they are dry or have any powder in them, replace it. You might have a bad centering ball or slip joint too.

I did not dent it. I can see some rotational scratches for about a 12" section. They are so minor I can't feel a groove.

I opened the caps, it was just black, there was little grease, I added some and put the caps back on.

Slip joint has a small amount of play. My Adams rear driveshaft has 0 play.

 

[DrDmoney]

Since my TT in April, I'm getting those nasty harmonic oscillating vibes under load about 65mph+. 4.0, 6-speed, 456 gears, JB SSSYE, Adams DC

I need some help with the CA's front and rear. I'm trying to get the angles right so I can decide if I need to go to the next step and clean or replace u-joints (how do you know if those are bad), and finally have one or both shafts balanced.

Front pinion = 8.5*
Front DS = 8.3*
Rear pinion = 17.0*
Rear DS = 17.1*

I tried to start with everything even, and I've adjusted the rear several times up and down and didn't change a thing. The front I adjusted this morning. Pinion was 9.3 and DS was 8.4 or so and the vibes were coming on at 62mph, so it's a little better now that they are closer to even. What adjustments would you make?

Mine is closer to what @Alex01 is running than what you have, hell yours is almost a straight shot, I’m at 8* pinion and 11* DS with a TW‘s X-Spline shaft. After the Atlas went in I test drove it and had zero vibes to 90mph so I left well enough alone. Sounds like something got bent or the u-joints are bad.

 

[JMT]

Mine is closer to what @Alex01 is running than what you have, hell yours is almost a straight shot, I’m at 8* pinion and 11* DS with a TW‘s X-Spline shaft. After the Atlas went in I test drove it and had zero vibes to 90mph so I left well enough alone. Sounds like something got bent or the u-joints are bad.

I need to check these things out for sure. I bet a TW driveshaft and some new U Joints would smooth everything out. Just another $350.

And mine is a straight shot now, I have it exactly at 8.5/8.5. The vibes are not too bad, but they definitely come on at 70mph.

 

[Apparition]

I need to check these things out for sure. I bet a TW driveshaft and some new U Joints would smooth everything out. Just another $350.

And mine is a straight shot now, I have it exactly at 8.5/8.5. The vibes are not too bad, but they definitely come on at 70mph.

Get the TW and keep yours for a spare.

 

[Alex01]

If you go with TW go with the X spline. The XB yoke, the one with the rubber cover, may be a better option than the XC for you since you're in a wet environment. With that said I bought the XB yoke and I tore the cover on my first trip in the rocks and should have just gone with the XC.

Hard to keep the TW X XB XC terms straight so hopefully that made some sense.

 

[starkey480]

Try 1* high on the pinion. The ujoint will be happiest there. Ie pinion at 9.5 and driveshaft at 8.5

 

[JMT]

If you go with TW go with the X spline. The XB yoke, the one with the rubber cover, may be a better option than the XC for you since you're in a wet environment. With that said I bought the XB yoke and I tore the cover on my first trip in the rocks and should have just gone with the XC.

Hard to keep the TW X XB XC terms straight so hopefully that made some sense.

Actually we only get 16.5" of moisture/year, quite dry on the East side. I'll go with the X spline, just like you. A little more dough at that price range can only be worthwhile. Thanks for that!

 

[JMT]

Try 1* high on the pinion. The ujoint will be happiest there. Ie pinion at 9.5 and driveshaft at 8.5

I just reviewed my notes, and I did NOT try the pinion that high. I will do that and see what happens. Boy is it it a picky driveline though. Thank you Garrett

 

[Alex01]

@bobthetj03 what's the rough caster calculation on the dana 30? I should really write it down so I don't need to keep asking.

 

[bobthetj03]

@bobthetj03 what's the rough caster calculation on the dana 30? I should really write it down so I don't need to keep asking.

12* - pinion angle. ie..... 12* - 6* pinion = 6* caster.

 

[Wildman]

Actually we only get 16.5" of moisture/year, quite dry on the East side. I'll go with the X spline, just like you. A little more dough at that price range can only be worthwhile. Thanks for that!

Hey now I'm on the eastside too... I think my amount is a little more as I get the inversion affect being so close to the mountains.


Man am I so glad I'd put hubs on my TJ back in the day. I got my Warn hub kit for fairly cheep back in 2002.

 

[JMT]

@starkey480 suggested I bump the pinion up 1* over the driveshaft. I made those adjustments today. Pinion at 10.1 and driveshaft at 9.2. Vibes are almost dialed out. I got up to 74mph before I thought I might be feeling some vibes. I may have a few more adjustments to make, but I think I can get this solved without another $$$ dump. Then I can focus on the XJ and tire size for the TJ. Goin' to 35's, yes or no? I don't know yet.

I also took a look at my MML in relation to the bracket on the passenger side. I have @mrblaine to thank for pointing that out a long time ago, but it just came back to mind and I thought to take a look. It looked like it was clearing, but it was very close and looked like it had touched and rubbed some. I worked an angle grinder and cut off wheel up over the lower control arm and trimmed some for additional clearance. There are less vibes in the cab overall, and the rig is running smoother overall for sure. Every little bit makes a difference as the nuances are worked out.