About to rebuild the rear end (IRS) any recommendations ?

2012Ridge

Member
Established Member
Joined
Nov 22, 2013
Messages
77
Location
Pittsburgh
Okay , So I had a previous post about vibrations and sounds coming from the rear end. It has been decided that it needs a rebuild.
The car is mostly street driven. Dunno if i'd ever take it to the track for a pull or not (most likely not). So with that in mind I figured I would run it by you guys and see what you think/recommend. Oh and car mostly only has bolt ons atm maybe a 2.3 twin screw later on at some point but for now it's just the bolt ons.

So here is what we are looking to order.

Ford Performance 31 Spline T-Lok w/Carbon Discs

Ford Performance 3.55 Gears

Ford Performance Ring & Pinion Installation Kit - With Bearings

Ford Performance Half Shaft IRS Bearing & Seal Kit

Ford Performance IRS Cover

FT 1200 Front Diff bushings

FT 1300 Rear Diff bushings

I'm wondering if this FT 1401 Rear Diff iso is worth it with the milled ford racing cover ?

While these things are being taken care of. Besides the Fuel filter are there any other things I should be taking a good look at ?

Thanks in advance
John
 
Last edited:

MG0h3

Well-Known Member
Established Member
Joined
Jul 23, 2014
Messages
13,862
Location
El Paso, TX
Do you have it apart already? If not, I strongly recommend you do before ordering all of those parts. Its possible all you have is a bad bearing and a simple rebuild will suffice.

When you mention the trak lok, are you talking about the whole differential? If so, Ive never seen the differential itself break, only a worn clutch pack. Its really just a casting, side gears, clutch pack, and a spring.

Id get with FTBR before ordering parts as you dont want to do just some of the bushings. I cant remember which mix/match you can do, might say on the site.
 

likuid_inc

New Member
Established Member
Joined
Aug 16, 2016
Messages
88
Location
New York
These IRS setups are a real pain in the @$$. Super expensive to play around with, I would stick with mG0h3 ^^^ and
make sure there is no cheap alternative to rebuilding the entire system. That full Tilt Boogie bushing kit is nice, but thats almost a grand right there.
 

2012Ridge

Member
Established Member
Joined
Nov 22, 2013
Messages
77
Location
Pittsburgh
Yeah, I feel the same way it is pricey. However I am kinda in a tough spot. I'm having a shop do the repairs. It has not been opened up yet. But i'm told the labor time to do the bearings and gears i am better off taking care of everything while he's in there. He did mention just maybe do the clutch packs but said it would be close to the same price with labor just to buy the diff. So i'm not sure what to do now lol. So to give you some more info on the rear end it had a leak front the front of the pinion flange. So I had a local mechanic change the pinion flange. Never removing the cover when doing the flange then topped off the oil. He did show me a finger full of metal flakes from the magnet. I figured your gonna have that?. Now when I started getting the Vibrations it was about 2 months ago. Also with the vibrations which start occurring around 40mph I started encountering a clang in the rear of the car. The clang has only happened 3 times. Twice when in forward motion coming to a stop. The second was in reverse pulling out of a parking spot slowly. So after going over this with the guy I am talking to now he said it's a good possibility that the mechanic who put the flange on, over cranked the flange and now the drive shaft has a bunch of play. So with the play I could be tearing everything up in there. So what do you guys think? I mean obviously i don't wanna over spend on what i don't need. But the parts would have to be ordered and this shop which mostly is all mustangs isnt gonna just let my car sit around in the garage while he waits for parts. So I feel my hand is forced.

Thanks for the help guys,
John
 

hotcobra03

Well-Known Member
Established Member
Joined
Mar 11, 2007
Messages
7,468
Location
poteet,texas
Front of diff bushings will cause alot of issues if still stock.

I had just redid my pinion shaft and ring..

In my driveway over nite..it wasnt hard at all.


its been about a year now..
 

MG0h3

Well-Known Member
Established Member
Joined
Jul 23, 2014
Messages
13,862
Location
El Paso, TX
Oh ok I remember your post about the banging when backing up.

I dont care if its a performance shop or your standard automotive shop, nobody should tell you to bring all the parts in before a diagnosis. Unless hes letting your bring your own parts? I guess thats different. But that makes me wonder what kind of shop this is.

If you dont have the tools and capability to rebuild the diff, I would really like to see you find a friend and pull it and take it to a rearend shop. Ive never dropped just the diff out but Im pretty sure you dont have to mess with the subframe at all. Just get the axles out, drives shaft out and youre good. Unless you have enough money that it wont hurt you but Im guessing youre looking at 2K with those parts and then the labor.
 

2012Ridge

Member
Established Member
Joined
Nov 22, 2013
Messages
77
Location
Pittsburgh
Yeah, taking the car to him next week. Mg apparently we had some miscommunication. He has me bringing the car to him next week to rip it down and find the problems. Before ordering parts.

Thanks guys I'll let ya know what it was.
 
Last edited:

P49Y-CY

fomocomofo
Established Member
Joined
Jun 21, 2003
Messages
11,228
Location
southwest
your list looks good, best of luck with the install. a nice addition might be a solid pinion spacer instead of the crush sleeve, but it's not absolutely necessary. and if you do end up needing a new lsd (and can afford it) the torque sensing diffs such as detroit tru-trac are a nice upgrade from stock.

yes the rear lowering mount is beneficial because it is the only way to match the driveline angle. unless you lower the rear of the differential you cannot adjust the front mounts enough to correct it. mismatched driveline angles can produce vibrations at speed.
 

MG0h3

Well-Known Member
Established Member
Joined
Jul 23, 2014
Messages
13,862
Location
El Paso, TX
Yeah, taking the car to him next week. Mg apparently we had some miscommunication. He has me bringing the car to him next week to rip it down and find the problems. Before ordering parts.

Thanks guys I'll let ya know what it was.

oh ok cool
 

2012Ridge

Member
Established Member
Joined
Nov 22, 2013
Messages
77
Location
Pittsburgh
Alright so the pics below tell the story on what was wrong with the rear end. I've been in good hands with mike at Wolfpack speed and he has been very helpful with the process. I decided while he is in there to do a FTBR 5001 Bushing install with the milled ford racing cover.
Also one of the toe links were bent so he is installing the FTBR toe links and sway bars. Hopefully when it's all said and done I come back with
the same happy results that all of you with the FTBR bushings have posted.

20161014_091158_zpstywkrbnm.jpg
 

2012Ridge

Member
Established Member
Joined
Nov 22, 2013
Messages
77
Location
Pittsburgh
Everything is back in the car. Full rebuild on the rear-end and full tilt boogie bushings with ftbr toe link and sway bars in the car. The rear-end really does feel like it's planted to the pavement now. It's kinda addicting to take a corner harder than I normally would now lol. It just feels great. I gotta get an alignment and tires but I've spent more than I was planning too already so I'll wait till next year for that. Going in the garage till spring. And 2 thumbs up to Mike at wolfpack speed he was a lot of help and gave me several options. But all in all a very good experience.
 
Last edited:

Users who are viewing this thread



Top