Goldenpony

I have an '06 GT 'vert I am thinking of having 4.10's put in. I am concerened because I have done gear swaps on 3 other Mustangs ('85 GT, '97 GT and '00 GT) and all 3 had vibration afterwards. I fixed them all by putting in aluminum driveshafts, butI don't want to do this on my '06. Any feedback?

Caution

I have NO problems with my 4:10 gears... I have FRPP if that helps ~ J

fordfanboy

Vibration from a gear swap is usually caused from an improper installation. Gears are one of the few parts I reccomend having done by a pro.

For example, many people complain that the Motive gears whine. Motive is a top notch gear and if you call Motive they will tell you themselves to ask your installer if he is comfortable with Motive gears before installing.

The reason they tell you this is the Motives are less forgiving than the FRPP's. That does not mean that they aren't as good. It just means that the instalation needs to be more precise over the fords for them to work effectively.

Gears and just about everything else in the rear end is critical for perfect instaltion and I always recommend using a pro for that stuff.

Goldenpony

I am familiar with everything you say. All my past swaps have been FRPP gears, and they were installed by "pros". I didn't have any whine, but just vibration like over 70 MPH. As I said, the aluminum driveshafts fixed the problems, but I just don't want to go that route with this car. Thanks for the feedback.

fordfanboy

Do you have the stock upper control arm?

Vibration over 70 should have nothing to do with the gears. It sounds like a pinion angle issue. Many times under load, the upper control arm will come just a hair loose and slightly change the angle and that will cause the vibration. It may be your case. I would check your upper control arm.

I had a similiar issue with my metco after I started making a lot or power. I welded that baby up and problem was solved.

Good luck.

2007GT/CS

Zero problems here.

Ironically, you are more likely to pick up vibration as a result of switching to an aftermarket driveshaft

moosestang

I had some slight vibration above 70mph. I fixed it by unbolting the driveshaft from the rear end and turning it 180 degrees. They also over tightened the bolts. No other problems after that.

Goldenpony

Thanks guys!

Caution

The way it was explained to me was -- if you have a lowered stang with gears... then the stock 2 piece DS is fine BUT if/ when you go with a 1 piece DS (Combined with the gears) then an UCA is needed as the DS will make your stang about 3 degrees off causing vibration.

We just had to adjust a friends stang as he added a 1piece DS w/ gears and UCA... the shop just forgot to adjust the UCA so we brought it right back for vibration ... adjusted 3 degrees and wahlaa... no more vibrations ~ J

FREAKO

Which way did you add the 3 degrees? 3 degrees so that the pinion pointed more upward or downward? My car is stock height with a vib issue on high speed deceleration (around 95 to 100 mph)