not so good vibrations

[natius]

I lifted my TJ about a year ago and put 35s on it. It ran smooth as can be, but needed lower gearing for wheelin. So just a few months ago I put in 4.56 gears, and ever since I get a vibration when I get up around 70-75 on the freeway. It is not a steady vibration with the RPMS or tire rotation. It vibrates on and off ever second in waves. It didn't do this before the gears, but now it does. Does anyone know how I can fix this without spending thousands of dollars? (besides not driving fast that is!)

-natius

 

[mbryson]

I lifted my TJ about a year ago and put 35s on it. It ran smooth as can be, but needed lower gearing for wheelin. So just a few months ago I put in 4.56 gears, and ever since I get a vibration when I get up around 70-75 on the freeway. It is not a steady vibration with the RPMS or tire rotation. It vibrates on and off ever second in waves. It didn't do this before the gears, but now it does. Does anyone know how I can fix this without spending thousands of dollars? (besides not driving fast that is!)

-natius

If you've checked your tires for balance and cord seperation, and your alignment, I'd wonder who set up your gears.

 

[bryson]

I lifted my TJ about a year ago and put 35s on it. It ran smooth as can be, but needed lower gearing for wheelin. So just a few months ago I put in 4.56 gears, and ever since I get a vibration when I get up around 70-75 on the freeway. It is not a steady vibration with the RPMS or tire rotation. It vibrates on and off ever second in waves. It didn't do this before the gears, but now it does. Does anyone know how I can fix this without spending thousands of dollars? (besides not driving fast that is!)

-natius

94" wheelbase plus 4-6" of lift equals about 90" wheelbase....with 35's....and no doubt a squirshy suspension....70-75 mph shouldn't be an option anyways....not saying I wouldn't do it, but if that is the only driveability problem you have, consider yourself lucky.

 

[Caleb]

94" wheelbase plus 4-6" of lift equals about 90" wheelbase....with 35's....and no doubt a squirshy suspension....70-75 mph shouldn't be an option anyways....not saying I wouldn't do it, but if that is the only driveability problem you have, consider yourself lucky.

this confuses me, I know what you are saying but when I had my wrangler as a DD I could easily do 70-75 with my 35s on and I never had any kind of issues...

 

[BOB-CAT]

Sounds like tires, find a jeep buddy and swap for a test. Next look at the drive lines. Last but not least take it back to who did the gear set up.

 

[sukaB]

If you havent changed anything except gears:I would ask who set them up,(qualified) and what gear brand did they use and did they use all new equiptment upon install. almost sounds like bad pattern or even more used gears if it's cyclical sounding...
Check your universal joints in the driveline..Pull a cap and eyeball the inside needles--Broken, worn, rounded edge..

 

[natius]

I had them done at Four Wheel Parts....can't argue with a half price labor sale. The question is did half price equal half ass? I took it back in and had them check the pattern, and they said it was fine. I replaced my joints, rotated, balanced, and alligned the tires. Vibration's still the same. If it were tires, I don't think the vibration would come in waves about a second apart. Once again, when the problem first occured, the gears were the only change in an otherwise consistent set up. Has anyone else run 35 inch MTRs with a 4-6 inch lift and used 4.56s, or lower and had the same type thing? Four Wheel Parts said it was the lower gear ratio and that because of the higher RPMs, it was expected. They recommended going to a short shaft to fix the problem. I've never known a short shaft to be the answer to any man's problems.

-natius

 

[I Lean]

I had them done at Four Wheel Parts....can't argue with a half price labor sale. The question is did half price equal half ass? I took it back in and had them check the pattern, and they said it was fine. I replaced my joints, rotated, balanced, and alligned the tires. Vibration's still the same. If it were tires, I don't think the vibration would come in waves about a second apart. Once again, when the problem first occured, the gears were the only change in an otherwise consistent set up. Has anyone else run 35 inch MTRs with a 4-6 inch lift and used 4.56s, or lower and had the same type thing? Four Wheel Parts said it was the lower gear ratio and that because of the higher RPMs, it was expected. They recommended going to a short shaft to fix the problem. I've never known a short shaft to be the answer to any man's problems.

-natius

What brand of gears did they use? Since you said 4WP, I'm going to guess Genuine Gears. I've seen some of those that COULDN'T get a consistent pattern on, anywhere.

Since that was your only change at the time, I'm going to guess gears. However, with the amount of lift you have, a slip yoke eliminator would be a good idea--though if it ran smooth before the gear change, it ought to run smooth after.

 

[bobdog]

At first I thought that it was just what happens when you make your driveshaft turn that fast, but when you say the vibration comes in a pattern every second or so I think it is the R and P. I sounds like a couple of the teeth just don't like to mesh and every time they work around to each other(The same teeth dont mesh every rotation of the ring gear) you get the vibe.

P.S. I have heard many horror storys about FWP gear setups. I would not let them set up my gears even if they paid me for the privelege.

 

[Greg]

P.S. I have heard many horror storys about FWP gear setups. I would not let them set up my gears even if they paid me for the privelege.

I'm one of those.

I had to buy a 2nd set of gears (Bought & Installed 2nd set from somebody else) after 4WPW installed my first set WAY too deep. The R & P ate each other untill they were junk.

 

[sukaB]

I'm one of those.

I had to buy a 2nd set of gears (Bought & Installed 2nd set from somebody else) after 4WPW installed my first set WAY too deep. The R & P ate each other untill they were junk.

Yah a cyclical sound is due to bad pattern or even more bad gears..
Spicer gears are the only gears that I use if availabale for the application...
If you do gears alot you know what I'm talking about...
They are very nice and the rest are just junk, or built kinda ****ty to be blunt..
How much would a half price gear install be frome them?????Just like to know-- since I don't shop there...

The short shaft is needed-I recommend them and is also a good safety
measure for rear driveline failure out on the trail..

 

[natius]

Very helpful......where were you four months ago?

You boys have helped a ton. Now I need to see if they can fess up to their crap gears at four wheel and help me fix the prob. The gears were genuine. The front were $227.50 the rear were $162.50 for the install. Wish me luck!

 

[jmaxj]

You boys have helped a ton. Now I need to see if they can fess up to their crap gears at four wheel and help me fix the prob. The gears were genuine. The front were $227.50 the rear were $162.50 for the install. Wish me luck!

If your dealing with FWPW your gonna need all the luck you can get.

FWPW is never wrong

 

[sukaB]

GOOD LUCK....
If I recall you said Sale prices? REALLY
I won't mention anything


Alright you twisted my arm..

If anyone putting in gears isnt trying use Spicer gears if available you should raise an eyebrow..
If they say sale prices you should raise an eyebrow...
my opinion.

Anyways good luck and I'll put my gears and detroits and such prices on my website soon...
:suka:

 

[natius]

OK, I am picking up some serious animosity towards 4W Parts. You boys seem to know your stuff. Where is the best place to get things like gears done? And for that matter, all other types of parts and accessories? I have had bad luck with Mepco as well. Where is the promised land?

-natius

PS ......and where can i get a hard top and some full doors for my TJ new or used for damn cheap?

 

[cyberduke]

OK, I am picking up some serious animosity towards 4W Parts. You boys seem to know your stuff. Where is the best place to get things like gears done? And for that matter, all other types of parts and accessories? I have had bad luck with Mepco as well. Where is the promised land?

-natius

PS ......and where can i get a hard top and some full doors for my TJ new or used for damn cheap?

Off the top of my head, I can think of 3 shops. All of them do GREAT work.

6 States Distributors. Talk to Eric or Andy. 801-488-4677
Rock Logic. www.rocklogic.com Carl or Von
Anarchy Off Road. www.anarchyoffroad.com Brandon.

All of these folks post on this board. I might also add that this is an unsolicited endorsement. I though not all of these folks have done work on my rig, I know them (some in passing) and what they can do. Seen examples of their work (or personally had work done) and know they stand behind it.

I should qualify. I'm sure there are other great shops w/ folks that post on RME. For me peronsally, these are the ones that I've seen work and have been impressed w/ and would pay to work on my stuff.

Sorry if this post wasn't kosher. It may be that this should have been in another forum.


-Earl

 

[Andy]

The cycling vibs are more than likely coming from the driveline. Do you have a SYE kit? If not that's probably why you are having issues, or maybe just a re-balance with the extra revs from the gear reduction. Just my $.02.

Andy

 

[sukaB]

Anarchy Off Road. www.anarchyoffroad.com Brandon.


Thanks Cyber.

I just recieved another jeep that has some 4wpw gear installs..
Yah I'm putting a rear 44 in, Detroit and gears in it cause the old set was setup bad and destroyed the whole rear end and ruined the diff..

This kind of crap sucks bad...