Vibration Starting at 70 MPH After New Parts
- Thread starter MaximusLJR06
- Start date
OP
Yes, I've had the front shaft out a good bit over the last month, but i will verify that again this weekend.
I went through that and eventually took a shaft out of one that didn't have vibrations and put it in mine and that took care of the problem.
I have one that was a little bit more of a beater so I put the shaft in it and sold it.
I can't remember if you have higher shaft speeds than normal when your regard but I tend to lean that it's usually around the front shaft and the double cardan most of the time but it's been proven that it can be a number of other things that cause vibrations.
We've had some guys on here that have really really fought it.
Typically the front pinion angle doesn't get off much because the point of rotation when it's lifted isn't changed just dramatically as the back is.. plus it's already a double cardan drive shaft
OP
Well hopefully when I get the old shaft back in I'll see a difference and know if its worth the rebuild on it. If it still has vibrations with the old shaft, I'm not sure what route to go then. From 0-65 my jeep rides smoother than it ever has in the 4 years I've owned it, hit 70 and its like wtf is going on.
I did see where Dennys driveshaft balances up to 10,000RPM where Toms and Adams only do to 3300RPM. That could be an option if needed maybe.
I do have the factory front driveshaft as well, I drove it cross country after buying the jeep without vibrations, but it needs rebuilt as well. It developed angry sparrows after I had the jeep for a year.
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You do not want one of those lock up on you... Man it will destroy the transfer case.
I struggled with solving this kind of vibration for years. Seems like around 70 mph was the starting point for me too. Had the front D/S balanced to no avail. Eventually got the angry sparrows, so rebuilt the driveshaft and brought it in for a rebalance to see if I could improve things. This time the run-out was checked and they found a slight bend in the shaft. It was straightened and rebalanced and finally solved my high-speed vibration issue.
OP
Yeah I know this already. That's why i pulled the adams out while I was in the mts and didn't wait till I got home. I'm thinking I'll be okay to test it though.
OP
Yeah, I'm struggling with why i have vibration now with all new parts installed but no vibration before when stuff was old.
That is the kind of thing that just makes you want to pull your hair out.
OP
Definitely!!! I have till the end of April to get it straightened, hope it doesn't take that long though. Getting married next month and then the honey moon is a road trip to Maine and Vermont with the jeep at the beginning of May. I didn't think id be a month and half in with issues still though.
I really hate that we don't have more affordable options to do manually locking hubs on these.. at the same time I like shift on the fly.... vibrations are not good for seals and everything so we are behind you 100%. Stay after it.
Sometimes you have to sit down with a woman and say honey I know we've been looking forward to getting married but I've got these vibrations with my Jeep.... And that's really a big priority for me right now.....
You can just about bet that will buy you some more time.
OP
Oh trust me, she's already fed up with how much time and money I've dumped into the jeep since December. I keep having to reminding her that we need it for the honeymoon.... that is slowly not working anymore.
I know how great Tom Woods drive shafts are, but every now and then one gets sent out that was not balanced correctly or at all.
I know this because it happened to me. After rebalance, and much heated discussion with them, I now have Adams 1350,s and Tom Woods on a shelf, hoping not to need it!
OP
Yeah, I would hope since this is the second one they sent out. It would have been balance and good to go. That’s the only thing that makes me thing I messed something up and didn’t install the control arms properly.
Anyway, I just got the old Adam’s shaft out of the garage and will give it a go this weekend.
for shits and giggles I measure pinion angles again this evening. Front pinion 8.5, front driveshaft 9.5. Rear pinion is at 7 and output shaft on the transfer case is 8. Rear driveshaft is 11.5 non cv. I’m assuming the front driveshaft angle keeps changing slightly cus I m not sitting level.
OP
Small update this morning.... had my tires rotated and balance checked. Vibrations still present at 70. They set tire pressure at 32 and the vibration may actually be more noticeable. @bobthetj03
below are the original driveshaft and the Adam’s driveshaft from the jeep. Not sure which one I should have rebuilt. Neither have vibration while in the jeep previously but both need rebuilt. CV have angry sparrows. I’m surprised how much longer the stock shaft is though. I greased the Adam’s up and am going to test it later this weekend.
below are the original driveshaft and the Adam’s driveshaft from the jeep. Not sure which one I should have rebuilt. Neither have vibration while in the jeep previously but both need rebuilt. CV have angry sparrows. I’m surprised how much longer the stock shaft is though. I greased the Adam’s up and am going to test it later this weekend.
OP
Another update. I just finished measure the axles for squareness. Front axle measured the same on both sides. The rear axle measured a 1/4” different, so I moved the passenger side of the axle the additional 1/4” back. Below are my rear pinion angle and transfer case output angle, which should be good to go if I am measuring at the tcase correctly. Heading out for a test drive now to see if there is any difference.
So if I'm looking at the photos correctly, you don't have a slip yoke. Is that a DC shaft? If so, we need to see the angle of the long section of the shaft. If it is a 2-joint shaft, and the pinion is angled higher than the output shaft, then I'd say you need to adjust the pinion down. Also, when measuring the tcase output, rotate the shaft so you can measure on one ear of the yoke.
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OP
It is not a dc shaft. It’s the stock lj rubicon shaft so just 2 u joints. I will try to get another measurement from the yoke. I was under the assumption that with a 2 joint shaft the pinion and the output should be the same angle? which from my current measurements they are.
After the rear axle adjustments for squareness, there was no change in vibration.