Hello everyone who has followed my post! I got car back today...this is what installer told me.He ordered a new set of FRPP gears....but he first redid old set again...with some changes to backlash and pinion depth...just to see what would happen. SAME THING!!! He took it all apart again...MEASURED Carrier,and Pinion Angle(which is 3 degree's on a stock suspension),and checked housing for trueness. Everything measured up true. He then put in new set of FRPP gears..set up to previous specs! CAR and Driver are happy again!!! Everything is fine...no clunking,and just a touch of whine on deacceleration,around 50-60 mph! Now i know some of you guys are gonna say you have no whine...and that's great...but all i can say is that it is a world apart from what it was before..and better than it was stock. I had whine both accel,and deaccel! His settings are as follows: Pinion Depth 28thousanths, Backlash 7 thousanths, and 7lbs preload on crush collar. Gears have nice even mesh to them. I don't know if this will help anyone...i hope so! CONCLUSION...must be something wrong with first set of gears!!!!!

 

That's awesome news, Fidele! I have new hope. My 4.10's are still singin' a tune. Haven't had a chance to bring it back in yet.

A few questions for ya:

Did you stay with synthetic lube?

How much of the expense did you incur? My installer has agreed to swap out my gears if the whine remains after switching back to dino lube. He didn't offer to do it for free, however. If your gears were defective then whose fault is it? Can't be yours. Right?

 

Fidele,
Happy to see it worked out for you I had the exact same experience as you. First set had a bad whine everywhere, second set has only a slight whine around 50 mph. FRPP needs to improve their quality control process.

The Boss Hog

 

Fidele, thanks for the update. I have two questions. First of all, did you get 4.10's? And second, I will be having my 4.10's installed in my auto GT in a week or two... can I tell the installer the pinion depth and backlash that you listed, to help him out? I have FRPP gears as well. Is every rear end different as far as that goes, or will those numbers work for me as well?

 

The directions were in the box with the gears on my 4-10s.Just let them do it. Mine whine a little but have no plans to redo it.

 

Clem...we stayed with the synthetic...as dino lube proved no change in whine. Good arguement as to climbing abilities of both lubricants...but i gues synthetic is better for bearings. I wound up paying 650.00 for the whole thing...and i know it's a little high,but this poor guy ate it on labor. For all his troubles..i think it was fair. This price was for bearing kit also..and a few lube swaps. Synthetic is expensive. His supplier has agreed to take back gears at no cost to him or i..so that's good! Gonna look into that "damper kit" supposedly offered by Ford...although my local dealer doesn't know what i'm talking about. Got the info here(TMS) The part number is 5r3z-3c246-a. Also...sounds crazy ..but these cars have like no sound deadener in them. Wheel wells resonate all kinds of road noise...even tiny pebbles can be heard hitting underneath. I'm gonna go in and Dynamat wheelwell areas. The stuff works great for keeping unwanted noise from interior. My whine is very slight now...but i think i can get rid of it completely!

 

I agree...It stinks for those who have to go through it! You really bang your head for awhile...lol! :bang:

 

The cure for this problem is to buy Ford Performance gears. I've had them in a couple cars and never once had an issue. You get what you pay for.


Whoops, I just noticed that you ARE using Ford gears. I'm shocked people are having issues. I'm sure everyone know this, but rears aren't exactly easy to set up. The people setting up the rear really need to know what they're doing.

I don't feel the problem is with the product. I think some installers need to be more careful.

 

Could be. For the record, Steeda did mine, first and second tries.

The Boss Hog