The previous owner of my mustang told me that the traction lok clutches in the car may need to be rebuilt because only one tire spins, he also added that the car would be dangerous with both tires spinning. Coming from someone who doesn’t really understand the drivetrain basics, what did he mean by this? What will happen to my driving experience if I rebuild the clutches (assuming I won’t do burnouts)
Drivetrain Question about rear differential clutch
- Thread starter dqureshi06
- Start date
So it loses traction more easily? It becomes more “fun” when you get on it?
It will perform better in every way with a good set of clutches.
The last time I rebuild mine, I stuffed an extra clutch and spacer in there (the best from the old set) to make it even tighter.
Cruising around on icy/wet roads with a traction lock and lot of power can get dicey. My recommendation there would be to learn to drive the car.
The last time I rebuild mine, I stuffed an extra clutch and spacer in there (the best from the old set) to make it even tighter.
Cruising around on icy/wet roads with a traction lock and lot of power can get dicey. My recommendation there would be to learn to drive the car.
Use good judgment when having fun, morons that don't 'drive' the cars to learn how they react do stupid crap.
Now, more important, pop the rear cover off the diff inspect for large pieces that look like it don't belong, seal the cover and fill with good recommended oil, there is a additive for trac-lock rears, go to a paved parking lot and drive in figure 8s first one way then the other. Only need a few times around, put a few miles street driving before enthusiastic application of the 'fun' peddle.
I have the extra clutch in both of my cars. Thread on it over on the corral explains how you get the space to add the extra one.
Video on how to replace the clutches:
Video on how to replace the clutches:
^^^ This is what you do to learn how to respond to a temperamental Fox with zero compunction about killing you.
All of the er... buttholes that you see plowing Mustangs into crowds have skipped this step.
Foxbody's are a driver's car, especially with a manual transmission.
With both tires spinning the car is quite a bit more fun and can also be more dangerous.
Snap oversteer is the real worry.
Normally i would say don't bother rebuilding a stock unit that's been on the car for 30 years, but a quick look and it appears 28 spline units are crazy expensive and 31 spline units only cost $300.
Rear end work is a slippery slope.
If it has stock gears, it's time to change to whatever you want and it certainly needs all new bearings seals.
If any axle whines (from worn axle bearings) you will need a new one and at that point it may just be better to switch to 31 spline.
With the axles out you may want to decide if you are staying 4 lug or going to 5 and if you are doing disc brakes.
I'll also add that it's not a beginners project and many times it's best left to professionals.
Not sure the going rate, but i can't see it being less than $500+parts.
With all that said, the car should be a blast with both tires spinning and a better gear ratio.
Just don't land up on youtube with a wrecked car.
With both tires spinning the car is quite a bit more fun and can also be more dangerous.
Snap oversteer is the real worry.
Normally i would say don't bother rebuilding a stock unit that's been on the car for 30 years, but a quick look and it appears 28 spline units are crazy expensive and 31 spline units only cost $300.
Rear end work is a slippery slope.
If it has stock gears, it's time to change to whatever you want and it certainly needs all new bearings seals.
If any axle whines (from worn axle bearings) you will need a new one and at that point it may just be better to switch to 31 spline.
With the axles out you may want to decide if you are staying 4 lug or going to 5 and if you are doing disc brakes.
I'll also add that it's not a beginners project and many times it's best left to professionals.
Not sure the going rate, but i can't see it being less than $500+parts.
With all that said, the car should be a blast with both tires spinning and a better gear ratio.
Just don't land up on youtube with a wrecked car.
Would it still be worth repairing if I don’t drive it hard or on the track? The actual installation of everything doesn’t seem intimidating but I drive my car pretty politely if it means anything.It will perform better in every way with a good set of clutches.
The last time I rebuild mine, I stuffed an extra clutch and spacer in there (the best from the old set) to make it even tighter.
Cruising around on icy/wet roads with a traction lock and lot of power can get dicey. My recommendation there would be to learn to drive the car.
You don't have to repair it... Its a performance item for Launching the car from a stop.. ... I don't believe running a worn out posi ( oops chevy talk here) will cause any damage... I would change the fluid though...
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You don't have to fix it. It would essentially be an open differential. Taking a corner and getting hard on the power might spin up the inside tire.
With a limited slip, when you spin up the inside tire, the outside tire will also receive power and try to push. Thing is is your rear end is nice and tight it will try to spin up the the same speed as the spinning tire and now you are staring down a crowd of grandmas about to become a meme.
Often times not enough friction modifier is used in which case the inside tire tends to drag a bit when making tight turns.
The diff in my 2000 is toast. No harm in leaving it but I plan on doing a stock rebuild with the M-4700-B kit. For my Fox i plan on doing the M-4700-C kit
With a limited slip, when you spin up the inside tire, the outside tire will also receive power and try to push. Thing is is your rear end is nice and tight it will try to spin up the the same speed as the spinning tire and now you are staring down a crowd of grandmas about to become a meme.
Often times not enough friction modifier is used in which case the inside tire tends to drag a bit when making tight turns.
The diff in my 2000 is toast. No harm in leaving it but I plan on doing a stock rebuild with the M-4700-B kit. For my Fox i plan on doing the M-4700-C kit
I’m planning on changing the fluid, so I’ll just go ahead and repair the clutches. I sometimes like to launch the car but I’m afraid of fishtailing after the new clutches so I’ll definitely be careful.
Well yeah... Part the fun is taking one or more of your best friends to a deserted parking lot and scaring the bajesus out of them while you learn to drive the car.
Pretty sure it's a requirement in our Terms of Service
Um... Pick one with no lamp posts Mkay? 
Its like snow skiing... If you don't crash, your not trying...... Just don't scoop up a butt full of snow on a cold day.....
manicmechanic007
5 Year Member
On snow or Ice in Virginia is when you will both love and hate the posi
I lived in Nordic valley (a ski resort in UT)
Used to drive my Camaro with a posi home in the winter around the golf course
Got to the corners and my front tires would just slide and the posi just drove the car absolutely straight off the road, onto the golf course a couple of times
It will make you be able to "go" with the posi, but it can also put you in a ditch
That is what the guy, et al. was talking about
I lived in Nordic valley (a ski resort in UT)
Used to drive my Camaro with a posi home in the winter around the golf course
Got to the corners and my front tires would just slide and the posi just drove the car absolutely straight off the road, onto the golf course a couple of times
It will make you be able to "go" with the posi, but it can also put you in a ditch
That is what the guy, et al. was talking about
Often times guys don't put enough friction modifier in when they do new clutches and refill the diff. If you are taking turns and the inside wheel is chirping or skipping or dragging, you need more.
