Brand new FRPP 3.73's have broken teeth! Need advice!!

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You are being feed so much BS it's not even funny. First of all, I don't see how a track lok would lock up. It has clutchs and would tend to slip in failure. What's more, if it did lock up, you would notice a squeel from the rear around corners and most likely the first thing to break would be an axle.

Obviously, he didn't do the install correctly or these bolts would not have backed out. I would bet he didn't correctly torque these bolts, which caused them to back out, which let the gears move around and break them. Installer error, I'd suggest having him buy you a new differential.

unfortunately for me, it's not FRPP's faulty gears, and wasn't my mechanics faulty installation. should a put a new differential in from the start.

well my mechanic was pulling the gears and traction-lok out today, and the tracktion-lok was locked up, and caused 3 of the bolts that hold the ring gear to the traction-lok to vibrate loose, which is the reason the teeth on the gears were missing. so I need a new traktion-lok, but I have no idea what to get. might as well beef it up, and make it worth my while.

so I need to know what do I get? (please provide a link if you can).

thanks in advance
 
You are being feed so much BS it's not even funny. First of all, I don't see how a track lok would lock up. It has clutchs and would tend to slip in failure. What's more, if it did lock up, you would notice a squeel from the rear around corners and most likely the first thing to break would be an axle.

Obviously, he didn't do the install correctly or these bolts would not have backed out. I would bet he didn't correctly torque these bolts, which caused them to back out, which let the gears move around and break them. Installer error, I'd suggest having him buy you a new differential.

instead of blaming my mechanic do something constructive like helping me find some parts, so i can get this back together, and get my car back on the road.

he torqued the freakin bolts to spec, I sat there and watched him do it.

dude has 33 years of experience, he knows how to work on a car, he knows how torque stuff down, he knows how to do rear gear installs.
 
mixedbreed....believe up that a T-lock cant lock up....or you would notice it. Only the clutch packs will slip. If it truely did lock up you would be chirping tires on every corner.
 
mixedbreed....believe up that a T-lock cant lock up....or you would notice it. Only the clutch packs will slip. If it truely did lock up you would be chirping tires on every corner.

so educate me then cause I sat there and watched him torque everything down good and tight he used locktite on them, his install was good, he measured the backlash, shimmed it properly.

something caused those bolts to come out.
 
The rear ends from the factory, oddly, don't seem to have a problem with the bolts backing out out. In fact, I have yet to hear of a single incident of this happening on factory installed gears. Funny thing.

It's great that you watched and all, but did you check the torque setting and accuracy of the torque wrench? Did you check that the bolt holes were all clean and dry? Did you check that the correct spec lock tight was used? If you did, I'm surprised you didn't get a fist to the face.

Differential Carriers - summitracing.com

You can shop all kinds of differentials. A Ford racing replacement traction lok is cost effective and reliable way to get you back on the road.
 
The rear ends from the factory, oddly, don't seem to have a problem with the bolts backing out out. In fact, I have yet to hear of a single incident of this happening on factory installed gears. Funny thing.

It's great that you watched and all, but did you check the torque setting and accuracy of the torque wrench? Did you check that the bolt holes were all clean and dry? Did you check that the correct spec lock tight was used? If you did, I'm surprised you didn't get a fist to the face.

Differential Carriers - summitracing.com

You can shop all kinds of differentials. A Ford racing replacement traction lok is cost effective and reliable way to get you back on the road.

no i didn't check the torque ratchet setting. but he did the whole thing with me watching, he used the red locktite which is the strong stuff.

these aren't factory gears either. these were FRPP 3.73's, and they were installed at 82,000 miles, i should have just replaced the damn diff to begin with.
 
did you have to order new gears or how is that going to come about getting them replaced?

i ordered the rear gears last week out of my pocket, they arrived Friday afternoon, which was too late to install them friday. so my mechanic got into it today, pulled the ring gear and the carrier, and the carrier casing is all torn to hell, so it has to be replaced. 2 bolts came out, and chipped 2 teeth off of the gears

the pin that goes through the middle of the carrier is all bent, and you can only get it about halfway out. so something happened inside the stock traction-lok when I was driving it to cause those bolts to back out, which in turn got caught between the gear teeth on the ring and the gear teeth on the pinion.

how that happened, we're not 100% sure. some people on multiple forums are saying it's my mechanic's fault and that he didnt torque those bolts properly. if that's the case then I have to ask why didn't all the bolts come out? why only 2 came out? They were all bolted down with a nearly brand new $300 Snap-On Torque Ratchet to spec. I sat there and watched him do it, he coated each bolt with lock-tite (the red colored kind), and bolted the ring gear to the carrier(posi/diff whatever the hell it's called).

on top of the $189 I just spent, I just spent another $500 in new Moser axles, and a new FRPP 31 spline Cobra LSD.

I want answers as much as the next person, but until I have some "definitive proof" as to who is at fault, I refuse to point fingers, and say "well it's your fault, you did it, so you pay for it".

My mechanic was moving some of the spider gears inside the Diff, and there was a lot of play in them, and I recall them being like that when we were putting the gears in the first time, and I remember him mentioning it as well, so maybe I should have just replaced the Diff or had it rebuilt before we did all of this. I don't know if that would cause enough vibration to throw the whole thing off and cause bolts to come out or not.

I went up and took some pictures with my camera...and I will have them up shortly.
 
sending the FRPP's back and I am going with a Moser 3.73

Just talked with a friend who owns a 91 Mustang GT with a 91.5 mm turbo pumping out 1400 hp, and he said he'd never use anything other than a Moser Ring and Pinion whether it be his street stang, or his drag Mustang and his mechanic who is a Pro Race Mechanic dedicated only to about 3 or 4 cars he works on at any given time echoed the sentiment on the rear gears and after seeing their car run numerous times I can't argue with experience.
 
I think your gears were just bad luck, I wouldn't really leave genuine ford parts behind after one incident....i mean, you are representing ford by driving their car

i really just think it was luck of draw...or mechanic messed up...either way, it was bad luck. like my ticket i got yesterday :D