Dacam

I haven't had any experience with FRPP gear sets or change a ring and pinion in a Ford 8.8 but for all my gear swaps in a Chevy 10 and 12 bolt rear ends, I always used Richmond. I never had a problem with obtaining a good patten. No whine or humming with load or coast.

I know that the "installer" is far more important than brand of gear set.

roblee121

ok i talked to the dealership ... they are saying the can do it in a couple hours so like $200. my next question is how much of a difference will there be between 3.55 and 3.73 or should i just make the jump to 4.10?

and if i jump to the 4.10 wont that KILL my top end?

2c5s

4.10 will change your RPM by about 300. 3.55 to 3.73 is not worth the expense in my opinion, it's about 100 rpm.

Alec

I'd say go for the 4.10s unless you're doing a ton of highway driving

Mishri

top end? i'd have to check a calculator but i'm sure you can still hit 160mph with 4.10s just get more power if you can't

i'd do 4.10s if I were you, most people that have them say they love them, most people who don't have them warn against them

and yes, your RPMs will be higher, you'll get worse gas mileage on the highway, i woudln't expect more than a 3-4mpg change though, thats what i saw in my 2007. but i also gained about 4mpg in town driving, some people say that isn't typical. though, i went from 15mpg in town to 19mpg and 25 interstate to 22.

as far as Dacam's experience with Chevy's and having a good installer doing them. Just read all of the old threads about gear whine, same installer, going from motive gears to FRPP corrected the problems people were having. just put gear whine in the search and read up. tons of threads on it.

Mikado463

So............what are the 'bad things' you heard about Ford racing gears ??

Derf00

I wouldn't do 4.10 just because the 2011's are a six speed. 1st gear is already worthless in a 5 speed (auto or manual) with 4.10 I can only imagine what a six speed with 4.10 gears would feel like.

parchisi

I'm honestly not trying to start anything, I'm genuinely curious, but I'm pretty sure that the same axle and differential has been used since I think '85, or whenever they stopped using the 7.5 for the 8.8. Yeah, the control arm mounting points and the axle length has changed, but otherwise I think its the same differential. What changed?

Cobrakev

Ok, here's the deal on the FFRP gears. Some of the gears made for FFRP, are made by Motive. These are the gears people are having problems with whining, and back lash. You can still get gears by FFRP, but the part numbers are different. I can't remember which are are which, but one of the part numbers ends with the letter "A". I read this a while back on another Mustang Forum. I will try and find the info, or you can call Ford and see what they say.

Kevin

Cobrakev

Just looked on FFRP website. They are now selling the 3.73 gears with the part number ending with the letter "N". These are a new design for the gears. The old gears FFRP sold came in two different part numbers. If you get the old Part numbers sets, they go as follows. 3.73 ending in "A" are the orignal Ford gears, made in the USA. 3.73 ending in "M" were made for Motive, but I think they were made in China. < not for sure made in China, just what I read. Hope this helps when ordering the gears. I would stay away from the 3.73 "M"s, have read to many bad stories about the Motive gears people had installed.