Rear end/trac lok issue

[Prospect62]

So I have my car up in the air to replace the rear air springs which were leaking. While it was up there, I did the old "spin the tire to see if you have trac lok" trick, fully expecting both tires to turn in the same direction because...ya know...every Marauder came with Trac Lok. Well...lo and behold, my tires spun in opposite directions. Now, either I got the only Marauder built without a Trac Lok or something is afoul in the rear end. The car makes NO rear end noise and is nice and smooth. I have not yet attempted a burnout.

Could worn Trac Lok clutches cause the car to fail the "spin the tire" test?

Also, I've read that the 28-spline Trac Lok carriers and spiders are Marauder-specific. If my clutches are toast, I'll probably just yank everything and put in a 31-spline carrier, 4.10's and 31-spline axle shafts. My question is, will any relatively recent (say 05+) cop car 31-spline carrier fit in this housing? I assume an 8.8 is an 8.8 and the 31-spline carrier will fit fine. It'd be nice to hear from someone here who has done it.

Thanks.

[mustangeddie]

Sounds like the clutches are wiped & don't be surprised if the spider gears are junk. Have done the 31 spline swap on both of my Marauders used 05-11 GM/Crown Vic axles & 31 spline Mustang trac locs it all bolts right in. If it has an open carrier someone swapped that in, all Marauders use trac locs.

[Prospect62]

Sounds like the clutches are wiped & don't be surprised if the spider gears are junk

That's what I figured. And yes, I'll more than likely use CVPI parts for my 31-spline swap.

"Plan A" will be to just open it up, replace the Trac Lok clutches and slap it back together. If the spider gears look bad I guess I'll start sourcing parts for a 31-spline swap, because I'm told the Marauder-specific 28 spline spider gears are not obtainable.


05-11 GM/Crown Vic axles & 31 spline Mustang trac locs it all bolts right in.

Thank you for the information mustangeddie.

[mustangeddie]

The Marauder specific spider gears are indeed unobtainable new. Any other 28 spline trac loc bolts right in & spiders are still available for them. If you must have Marauder specific ones I do have a few good used ones & a whole Marauder 28 spline trac loc but if it were mine I'd just do the 31 spline swap & be done with it. Also the early cars are known to trash the axles my 03 built in July 02 wrecked them @62k which is why I did the 31 spline swap.

[Prospect62]

Also the early cars are known to trash the axles my 03 built in July 02 wrecked them @62k which is why I did the 31 spline swap.

Not sure what to do, kind of at a cross roads. The car has 306,000 miles on it and it has ONE (YES ONE) replacement Yukon axle on the driver's side. While I'd like to just do the 31-spline upgrade, it's really not necessary for my needs for this car.

Let me take a look at what I have in there and I may take you up on some or all of those 28-spline parts. I'd rather not change the carrier and all if I do decide to stay 28 spline.

[justbob]

You can upgrade just the carrier guts and axles to 31 spline without removing the carrier. Easier and a plus if it has 4.10’s.


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[Prospect62]

The 28-spline carrier accepts the 31-spline side gears and spider gears?

[mustangeddie]

The 28-spline carrier accepts the 31-spline side gears and spider gears?Not as far as I know.The pin in the 31 spline is .875 a 28 spline is .750 so the spiders are a definite no go.Maybe mixing 31 spline side gears with 28 spline spiders works idk never did that.I know 80's & 90's versions of the 31 spline carriers you could not do that the 31 spline spiders were bigger than 28 spline, maybe the later ones that is possible but in my mind kind of half defeats the purpose of changing to 31 spline when some of the parts are still the small stuff from the 28 spline unit.

[Prospect62]

Not as far as I know.The pin in the 31 spline is .875 a 28 spline is .750 so the spiders are a definite no go.Maybe mixing 31 spline side gears with 28 spline spiders works idk never did that.I know 80's & 90's versions of the 31 spline carriers you could not do that the 31 spline spiders were bigger than 28 spline, maybe the later ones that is possible but in my mind kind of half defeats the purpose of changing to 31 spline when some of the parts are still the small stuff from the 28 spline unit.

OK, thanks. That's what I figured.

[justbob]

I’ve personally done it and it was a very straight forward easy process. I know I had all the spiders, pin, cobra clutches, and spring on hand but I honestly can’t recall if I used it all or not as it’s been many years and I have problems remembering yesterday..


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[03Merc]

So I have my car up in the air to replace the rear air springs which were leaking. While it was up there, I did the old "spin the tire to see if you have trac lok" trick, fully expecting both tires to turn in the same direction because...ya know...every Marauder came with Trac Lok. Well...lo and behold, my tires spun in opposite directions. Now, either I got the only Marauder built without a Trac Lok or something is afoul in the rear end. The car makes NO rear end noise and is nice and smooth. I have not yet attempted a burnout.

Could worn Trac Lok clutches cause the car to fail the "spin the tire" test?

Also, I've read that the 28-spline Trac Lok carriers and spiders are Marauder-specific. If my clutches are toast, I'll probably just yank everything and put in a 31-spline carrier, 4.10's and 31-spline axle shafts. My question is, will any relatively recent (say 05+) cop car 31-spline carrier fit in this housing? I assume an 8.8 is an 8.8 and the 31-spline carrier will fit fine. It'd be nice to hear from someone here who has done it.

Thanks.

The Marauder has a LSD carrier, it's not a locker unit or else it would chirp tires when turning corners. The LSD allows one wheel to move more than other to avoid chirping as far as I know. And for the one wheel going forward and the other one backwards, I believe that's normal as well. If You spin the driveshaft while in neutral then I believe they both may spin in the same direction.


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[Turbov6Bryan]

Go do a burnout and see if it makes 11s

[blazen71]

"IF" you just rebuild the 28-spline, take the carrier out and do the work on the bench. You can put the carrier back in with out any shimming issues, as long as you put the correct shims from each side back in the way you took them out.

[massacre]

What does the axle tag say?

[Prospect62]

"IF" you just rebuild the 28-spline, take the carrier out and do the work on the bench. You can put the carrier back in with out any shimming issues, as long as you put the correct shims from each side back in the way you took them out.

Looks like I could do the clutch packs with the carrier in the car, but if it breaks my balls I sure will. Good advice, thank you.


What does the axle tag say?

I didn't take a good look at it. But I have to assume it says 3L55 as that's the only thing Marauder's came with. Unless the whole rear axle has been swapped...

I'll check and get back with the results!

[blazen71]

It's 4 more screws to take out the carrier, just do it and spare yourself any struggle.

[daniel.drives]

I replaced the clutches with mine still in the car. Best advice I can give is that a large hose clamp works well to compress the S spring in the middle. One replaced axle is weird, hopefully the previous owner(s) weren't too much of cheapskates.

While it's all apart, it's probably worth pulling the axles and replacing the wheel bearings and seals at the same time. My car with "only" 200k was dripping on the barrel of the rear wheel.

I've since managed to kill that set of clutches, between racing the car, not changing the fluid for 5 or 6 track days, and overfilling by .4 qt (I neglected to actually read the directions and just filled to the fill port) I suspect it's gotten quite hot.

Unrelated, but at your mileage, unless you know for certain the status of the timing chain guides and tensioners, you should definitely replace them. IF the recommended maintenance has been followed, you'd be installing the 4th set in the car's lifetime

[Prospect62]

I replaced the clutches with mine still in the car. Best advice I can give is that a large hose clamp works well to compress the S spring in the middle. One replaced axle is weird, hopefully the previous owner(s) weren't too much of cheapskates.

While it's all apart, it's probably worth pulling the axles and replacing the wheel bearings and seals at the same time. My car with "only" 200k was dripping on the barrel of the rear wheel.

I've since managed to kill that set of clutches, between racing the car, not changing the fluid for 5 or 6 track days, and overfilling by .4 qt (I neglected to actually read the directions and just filled to the fill port) I suspect it's gotten quite hot.

Unrelated, but at your mileage, unless you know for certain the status of the timing chain guides and tensioners, you should definitely replace them. IF the recommended maintenance has been followed, you'd be installing the 4th set in the car's lifetime

I'm trying to wrap my mind around how you'd get a hose clamp off the spring once it's put back in the carrier!

The timing chain guides and tensioners were just done last year.

I know, really surprised to see just that one Yukon axle in there because the car was quite clearly taken very good care of. No leaks or noises currently, but bearings and seals are a good idea, I'll probably do them.

Once I get it open, I gotta see what kind of shape the spider gears are in. If they're shot, everything is coming out for a 31-spline swap anyway...and if I do that, I'll probably put it back in with 3.90's. See how slippery the slope is??? If the spiders and side gears are good, I'm slapping new clutches in it and sending it like Ford made it until I have a reason to upgrade to 31.

[Prospect62]

It's 4 more screws to take out the carrier, just do it and spare yourself any struggle.

I just did inner axle seals on my K5 Blazer, necessitating removal of the carrier. I'm aware of the process. I just hate taking out carriers and shims if I don't have to. I guess we will see how it goes. If I have to take it out, I will. NBD.

[blazen71]

I'm trying to wrap my mind around how you'd get a hose clamp off the spring once it's put back in the carrier!


Cut it with shear or side cutter

[SilverPhoenix]

Once I get it open, I gotta see what kind of shape the spider gears are in. If they're shot, everything is coming out for a 31-spline swap anyway...and if I do that, I'll probably put it back in with 3.90's.

I don't race my MM or have much mechanical knowledge, but I just wanted to say if you decide to swap out the gears to go ahead and put in a 4.10. I had that done to mine and got it tuned and the difference was amazing to me; I still have the orig 28 spline axles. MPGs didn't drop much...from 18-19/24-25 to 16-17/23-24. I realize your end goal may be to just get the rear end all squared away so you don't have to worry about it, but I just wanted to give my 2 cents about the gear swap.

[Prospect62]

Well, I figured out why both wheels aren’t spinning. Looks like someone replaced the carrier with an open unit at some point. I assume the reason was the original spider gears wore out and since they’re no longer available, someone thought a fun solution would be to put in an open 28 spline carrier instead of a Trac Lok.

Now the question is do I just slap it back together and live with it or do I find a trac lol carrier and some 4.10’s and take it somewhere for a swap? I found a used Trac Lok carrier with a 4.10 ring and pinion…I’m debating just swapping that in and sending it but I’ve never set up gears before.

Bottom line…WTF. Why does stupid stuff like this always find it’s way to me?52151

[Mr. Man]

If your just going to use the car for putt-putt putting around I'd put an LSD with 4.10 or 30's in it. If it's a DD, dealers choice for the 3.55 or 4.10's. 4.73's seem like a waste between the other two, but that's an option as well. My :twocents:

[SilverPhoenix]

"Now the question is do I just slap it back together and live with it or do I find a trac lol carrier and some 4.10’s and take it somewhere for a swap? I found a used Trac Lok carrier with a 4.10 ring and pinion…I’m debating just swapping that in and sending it but I’ve never set up gears before."

Tried the 'reply with quote' function and it wouldn't work...

Sounds like you have the opportunity to have 2 options; you could slap it back together and live with it AND you can get the used TLC with 4.10. That way, if you decide later on down the road you don't want to live with it you have a TLC with 4.10 on hand to swap in. If after a while you do decide to live with it and don't think you'll ever swap in the TLC with 4.10, I'm sure you'll be able to find someone to take the TLC w/4.10 off your hands.

Better to have it and not need it than to need it and not have it...or want in this case...

[Prospect62]

Well I planned to do 4.10’s anyway. Todays development is just forcing my hand. In my last three crown Vic’s, I’ve paid someone to install 4.10’s. I’d really like to try to install this used TLC with 4.10’s myself. I have all winter, car will be in the garage.

I’m wondering how big a deal it would be swapping in this used carrier, ring and pinion as I’ve never set up backlash and all that jazz before.

[RubberCtyRauder]

If not set up right it will whine and heat up and cause issues. 4.10 will require a tune so add another $500+ for that if you don't have an SCT unit. If you do, then about $125 for new tune. Speedo will be off and and shift points will be off. Look on car-part.com for an 06+ CVPI with 3.55 gears, direct swap and has 31 spline axles

[Prospect62]

If not set up right it will whine and heat up and cause issues. 4.10 will require a tune so add another $500+ for that if you don't have an SCT unit. If you do, then about $125 for new tune. Speedo will be off and and shift points will be off. Look on car-part.com for an 06+ CVPI with 3.55 gears, direct swap and has 31 spline axles

Im aware of what the 4.10’s will do and require. As I said I’ve done them on 3 other Panthers. Doing the cop stuff is an option but it’ll still require proper set up and shimming just like a 4.10 set would. Might as well do the 4.10’s.

[SilverPhoenix]

Well I planned to do 4.10’s anyway. Todays development is just forcing my hand. In my last three crown Vic’s, I’ve paid someone to install 4.10’s. I’d really like to try to install this used TLC with 4.10’s myself. I have all winter, car will be in the garage.

I’m wondering how big a deal it would be swapping in this used carrier, ring and pinion as I’ve never set up backlash and all that jazz before.

Weird...the reply with quote function worked this time...

Well, all I can say is when I had mine done it took the guy just shy of 3 hours, IIRC. I even created a thread about it here under my previous name IwantmyMMnow; took some pics and whatnot. I think I'll go look that up now and take a quick trip down memory lane...lol. Sounds like you should be able to handle it just fine since you have lots of time to make sure everything is done correctly.

[Prospect62]

Well, I figured out what's going on here, thanks to the help of mustangeddie.

This IS in fact, a 28-spline Trac Lok carrier but whomever rebuilt it last (it's been rebuilt I can see punch marks in the bearing caps and housing) forgot to put the "S" spring back in (or left it out on purpose - I hear the Mustang guys do that). So that explains why it's a one tire fire. I jumped to conclusions when I didn't see the spring in there or the clutch "ear" tabs. I now know that the 2003+ Trac Lok housings "hid" the clutch ears inside the carrier.

Good news is everything looks pretty decent, including the spider gears which I was told tend to wear badly. At 306,000 miles who really knows who did what to this car. I'm sure there's not much of it that hasn't been touched already and not much that's still factory.

So anyways the plan is I'm going to replace the limited slip clutch disks with original equipment clutches from Ford (since I ordered them already), slap a spring in there and just run the 3.55's for next summer and see how it goes. Since I've wanted a Marauder for so long, I kind of want to experience the car as Ford intended it for a season before I go making it into a rip-snorter anyways.

When I have the money for a gear swap and Marty tune I'll do it down the road (it's definitely on the list Marty in case you're reading this). Thanks everyone for the input on this and the help.

PS - don't mind the dirt that fell onto the gearset. I cleaned it out.

[RubberCtyRauder]

You can still get a Marty tune with 3.55. it wakes the car up and corrects the poor factory shift parameters. When you do 4.10 gear swap, it's just a tune revision for minimal cost. You'll already have the SCT. Tune can be emailed.

[Prospect62]

I've purchased two Marty tunes and put 4.10's in two Crown Vics (and a 5-speed in one of them). He's awesome to deal with but I think I'll just do it all at once and save the $150 revision fee.

[SilverPhoenix]

Glad to hear you got it all figured out. I never had my MM tuned before I swapped out the 3.55 for the 4.10, so I don't know what the difference is between the factory 3.55 tune and a custom 3.55 tune; I do have a custom 3.55 tune loaded on my SCT though...lol. I just remember that after I had the 4.10 installed and the tune loaded I was able to chirp the tires on the 1-2 shift, which I had never been able to do before so I was all hyped about that.

Congrats again on your 'new' MM and hope you enjoy cruising around in it!