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Limited slip rear end question

The rear in my car is starting to only spin one tire.  My question to you guys would be is this something I could remedy myself?  Is there a better alternative for the 8.8 rear end then going with the stock limited slip?  Kinda sad when you hit it and only leave one mark.  The mileage on the rear end is about 125k miles.  I have a rear end from an 88 TC I could swap in that I know the limited slip is still working in but I would rather not rob that for parts and risk not putting it back together correctly.
84 TC - under contruction
2018 F150 2.7 4x4 STX
98 F-150 XLT - 4.6, auto, 4x4, extended cab

Limited slip rear end question

Reply #1
I rebuild them in the car and adding an extra clutch and a truck wave spring. But some people have a difficult time doing this. It is not hard to do but the big question is will the cross pin retaining bolt come out. That is if it is not broken. That is the issue. You can buy new packs but personally i can buy a complete Ford motorsport HD carrier for a few dollars more and that is what we do now. This way everything is up to speck and brand new. Have a great day guys
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Limited slip rear end question

Reply #2
Hey Tom,

When you replace the clutches are there any special measurments or tools you need?  Is there a link to purchase this with instructions?  How much would you estimate a reputible shop would charge to rebuild the rear?  Im fairly mechanically inclined, just not very good with electricity, so I would think about trying this myself if the directions are fairly easy to follow.

Thanks!
84 TC - under contruction
2018 F150 2.7 4x4 STX
98 F-150 XLT - 4.6, auto, 4x4, extended cab

Limited slip rear end question

Reply #3
Quote from: croga001;438609
Hey Tom,

When you replace the clutches are there any special measurments or tools you need?  Is there a link to purchase this with instructions?  How much would you estimate a reputible shop would charge to rebuild the rear?  Im fairly mechanically inclined, just not very good with electricity, so I would think about trying this myself if the directions are fairly easy to follow.

Thanks!


Not sure about Tom's method, but to swap out clutches I imagine he must be removing the differential anyway, so here's a write-up with a list of tools/equipment you'll need:

http://www.corral.net/tech/drivetrain/gears.html

I can't vouch for that procedure, but the list of items needed is pretty comprehensive.  The more uncommon items were about halfway through the list - the calipers and travel dial indicator, and are probably the most important items you'll need/can't do properly without.

Good luck!

Limited slip rear end question

Reply #4
You do not have to remove the carrier. just the axles ans wave spring and spider gears. The rest is easy. Pack kits are available from ford and other places like randys. It is a little tricky installing the wave spring but not that hard once you do it. Have a great weekend guys.
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Limited slip rear end question

Reply #5
Drain the rear end, remove the rear differential cover, remove the pinion shaft bolt (8mm wrench), remove the pinion shaft, slide one axle all the way in and remove c-clip, slide same axle back so that is clears the spider gears or remove completely, and repeat for the other axle.  The steel plates and clutches which make up the limited slip or in Ford's case the Trac-Lok are behind the spider gears that the axles slide through.  Typically there is enough room to add a steel plate and an extra clutch on each side which creates more clutch surface area which in turn creates more friction.  The "Z" spring that Tom is referring to is what preloads the spider gears so getting the one for an F-150 creates a higher preload as the spring is much stiffer.  This is good for the posi affect and you will need to use friction modifier additive even if the gear lube says is already has it as it will not be enough.

Do a search on You Tube and there are several good videos of guys rebuilding the Trac-Lok and its something almost anyone with the right tools can do in the garage with the rear end in the car.

This is about as cheap as you can find for just the kit:

http://www.latemodelrestoration.com/item/LRS-4700A/Mustang-Ford-Racing-88-rear-end-Traction-Lok-Clutch-Kit

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Limited slip rear end question

Reply #6
Heat the housing where the bolt go's in for the crossover pin, there known to snap off.
Old Grey Cat to this.88 Cat, 5.0 HO, CW mounts, mass air, CI custom cam, afr165's, Tmoss worked cobra intake, BBK shorty's,off road h pipe, magnaflow ex. T-5,spec stage 2 clutch, 8.8 373 TC trac loc, che ajustables with bullits on the rear. 11" brakes up front. +

Limited slip rear end question

Reply #7
What would heating it do. If it is already busted the heat is useless. It does not break because it is frozen in the carrier it busts from cross pin hammering.
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Limited slip rear end question

Reply #8
I had one break off at the threads with a couple of threads still left on the pin.  By some miracle I was able to use a pick and Liquid Wrench to get it out but it took about an hour and some cussing.  I talked to the Ford tech and he said is it hit and miss on cars they work on and it seems like they have more issues with rear ends that have been into versus ones that were factory.  One thing he told me is that they never reuse one of those bolts, they throw it away and install a new one.  I have a couple in my tool box as I have taken that approach to heart and have never had a problem with one since.

I've got a couple of buddies that will reuse them and have not had any issues either so it could just be that the one time I had an issue someone over tightened the bolt.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Limited slip rear end question

Reply #9
Never reuse them. I also had some do what you describe. Also on other cars like GM ETC.
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Limited slip rear end question

Reply #10
over the winter I had slid on snow and hit a guardrail. come to find out my trac-lok wasnt working, was only spinning one tire.

Well ended up my rearend was over full and just needed drained a bit and needed the anti slip additive as my brother didnt put it in when he changed it. fixed it right up.

Limited slip rear end question

Reply #11
If this is the 7.5 rear track lock don't remove the carrier unless you are gonna rebuild the entire rear end.  They will not last without a backlash and shim.  (I've ate up at least 6 rear carriers).

A hot wrench is your friend.  Heat up the pin where the taper bolt retainer is before you try wrenching on those.  They are one of the bigger issues.  (The 3/8 or 8mm bolt)  Don't force it they snap and round easy.

I've also just did a gear oil change on them with friction modifier and it's prolonged the original 30 year old clutches.  It's like 7oz recommended for the 2 qts of gear oil.  I recommend only using like 5 though, that stuff is strong and not to be used wrong. (lesson)

Good luck and good deals.
84 TurboCoupe with 302 .010 over - 9.8 : 1 Forged Pistons - Edlebrock Goodies:  Aluminum Heads #6037, Intake #3821, 65mm TBI/EGR #3824/3827, Camshaft #3722 -  Interactive System & Technologies Mass Air with 24# Injectors - A9L - 3g Alternator - BBK shorties, Cat Converter H-pipe, Magniflow lers - World Class T5 1352-169 (1986, V8, WC, 3.15 3.35 1.93 1.29 1.00 0.68) OEM Clutch Cable - 7.5 Trac Lock with 3.08 and slapper bars from 82 Mustang.

 

Limited slip rear end question

Reply #12
I've never had one break, but I use a 6-point box end wrench and a quick, light rap with a dead blow hammer (element of surprise attack). I think some of the ones that break are from the pin end being a micro-smidgen too long, then they bottom out and end up stress-fracturing under use..... I use a new cross-pin and grind a tad off of the pin end.

Limited slip rear end question

Reply #13
They break before they are removed. The cross pin chatter breaks them. Their is plenty of depth no need to trim them. And once again in 50 years in this business i never had to heat one. They are not that tight. Unless someone got carried away. And i rebuild the 7.5 all the time with absolutely no issues . Why would the settings have to be changed??? Tapered BOLT. News to me??? And i have built a couple in my day.

http://shop.cruiserparts.net/index.php?main_page=product_info&products_id=12378
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!