the_pony_express

So my 3.73 gears and T-Lok should be arriving in a few days, and I was just wondering what I should expect when I have them installed.

I've heard numerous things- the gears shouldn't whine at all ever; a little gear whine is ok, it will go away; if your gears whine there's no way to fix them without another install; etc, etc. I hear of people with flawless installs, and those not so much.. I will be having them installed by my local Ford dealership, so I would hope they know what they are doing, but you just never now. Also, they are Motive gears.

So my questions are:

What is the truth behind gear installation? Should there be no whine? Is whine ok for a while?
If my gears DO whine after install, what should be done? Demand them to be fixed? Take their suggestions and try to "drive it off"?

All answers are appreciated; I just don't want to have to live with a regret of getting these mods.

groved

First off, I dont know.

Secondly, my question is... If you get the work done at the Ford Dealership is it covered under warranty?

I would guess not since your not using original factory gears but once again, I don't know.

28HopUp

What should you expect after a gear install? A painfully long break-in period

When I had the 4.10's and t-lok installed into my 7.5" rear, they whined. It did get better over time, but they definitely added some music to the symphony of car noises. I had no trouble with the add'l noise, but mine weren't THAT bad.

You'll love having new gears!

157dB

http://iihs.net/fsm/?dir=83

It all depends on the brand of the gears.
Some are inferior and will whine no matter
what.
I think that Motive are the worst and some
sold as FRPP are actually Motives in a Ford box.

You shoulda went for the 8.8 rear end with
the 3.73s and T-Loc already installed along
with the V6 pinion flange.
The cost of the7.5" gears and T-Loc and install
equals a fully set-up 8.8" with the V6 pinion flange.
After its all said and done, you coulda had an 8.8"
with 3.73s and a T-Loc instead of the 7.5" rear end.
Reworking the 7.5 rear end is a waste of time IMHO.

Avoid whiney Motive gears. They are stamped with a M.
Some FRPP gears have been known to be made by Motive,
packaged by FRPP and sold as FRPP gears.

mignella254

I just bought and installed some 4.10s and t-lok on my 7.5 inch:

They're fine. the differential is ford racing and the gears are Richmond. I wish someone would have told you to stay away from the motive gears, they're cheap, and whine, a lot.

In a perfect world the gears should not whine at all, but a little whine isn't necessarily a bad thing. Just take it for a test drive after the dealership is finished with the install, and if worse comes to worse, take it back and tell them to do it until they get it right.

ruprect108

I got Motive 3.73. They did whine ALOT at first to be honest but finally that has mostly gone away. With WOT I can still hear it but not really at almost any cruzin speed.

Sancho805

expect good things!.... unless they whine like a g/f.

jdphillips73

i installed 4.10's on my f-150 in my driveway.... no whine whatsoever from the get-go... one year later, quiet as a baby sucking on his mommas nipple.

I installed ford racing with yukon bearings

4.0 $tang

i have motive 3.73 gears and frpp t-lok...i have no whine...you gotta take it to a good shop, my local guy is awesome so i had no worries...if you buy all ford parts and have it installed by the stealership, they should honor your warranty...but they can also say they don't have to because some frpp parts are considered "off-road use only" and don't carry any warranty

DAVEAUSTIN

I have 4.10 Motive gears with the t-loc and I have no whine...I went to a place that only does customization work...