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Discussion Starter #1
14 gt premium
6 speed mt82
dss driveshaft
Bmr lower control arms, upper control arm, uca mount, relocation brackets, Panhard bar, and bmr sway
Ground control's coilover kit.
Mgw racespec
amsoil mtg fluid

The vibration I'm having is a small one yet noticeable. It is cyclical. It goes 1-2-3 pause for 1/2 of a sec and repeat.
This only happens at 75 mphs plus or minus 3 mph.

I noticed this after the mgw install. Months after. Because I didn't cruise at that speed. My first thought was the driveshaft, so I replaced it with the stock one. Still there.

The rear end has factory 3.73s the axle tubes are welded and were done so at a driveline shop in a jig.

I ran the car on jack stands under the tubes and yep its noticeable. You can feel it in the the body of the car too. I could feel it in the door. The body panels. It was not as bad on the bottom of the trans or bottom of the diff.

Only real reason I noticed it is is the shifter.

Soooo... what's up. What can I check out cause I'm getting at a lose with it.
 

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11.5:1 or GTFO
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Don't know. I'll come take the one piece off your hands this weekend though.
 

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Discussion Starter #3
It's sitting on the garage floor at the moment. To bad that wasn't the cause tho. Wouldve been easy to send back to dss and have rebalanced.

I'm thinking it's something in the rear end
 

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Biz Jet Fixer
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Did you watch your tire as you ran it on stands to ensure you don't have a bent axle?
Pinion angle set correctly?

I've had a very minor vibration for forever and have never been able to pinpoint it, I have no concern with it though.
 

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Discussion Starter #5
I watched the left side but didn't look at the right. That's one thing I didn't think of.

The pinion angle is either -1 or -2 degrees difference from the trans. But with the dss it has a cv joint and dss says not to worry about the angle
 

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Biz Jet Fixer
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I watched the left side but didn't look at the right. That's one thing I didn't think of.

The pinion angle is either -1 or -2 degrees difference from the trans. But with the dss it has a cv joint and dss says not to worry about the angle
It does (I have DSS) but I'd still try to get it around the -2 point. It could possibly be part of the issue. Idk.
 

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Discussion Starter #7
It's set at what bmr recondmends for a manual car. I set it there when I installed the suspension stuff first go round. Never had an issue.

The stock shaft is it it at the moment and it still has the vibration. I figured if it was drive shaft related it would have stopped when I put the stock shaft back in.

---------- Post added at 08:51 PM ---------- Previous post was at 08:51 PM ----------

I'll still try to mess with the pinion angle tho
 

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I know that there were a lot of bent axles on many cars from the factory.
 

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Tell that to the guys who have gear whine and have had rear gears replaced over 3 times under warranty, then bearings, etc... Finally they end up having the whole rear end changed out, which they only get the parts to rebuild them, and they find out they had a crooked axle.
There are tons of these posts with Boss guys and PP cars with 3.73's.

 

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Zip's half naked helper
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If that were the case, I'd probably have seen a few by now, given my particular line of work.

(Here's a hint- the shop I work at has this great big blue oval out front, there's usually these guys running around like blubbering idiots you could call salesmen, and the plaque on my toolbox says something along the lines of Senior Master Technician. But what do I know, right?)
 

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Glad you haven't had to try to fix any of those. What can I say.
 

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Discussion Starter #13
Whatever the case is with the bent axles out of the factory, his mentioning of it has gave me another clue to what it may be. Now I can check the run out on the axle flanges to see if one may be bent.

That and the pinion angle will be checked this weekend
 
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