MMX Driveshaft install

[Svashtar]

Sorry to ask if this is obvious to all of you, but I did do a pretty comprehensive search of the forum and didn't come up with a hit on this install topic: how difficult is the R&R of the OEM driveshaft with the MMX shaft? I just got this in from Dennis and haven't eyeballed it as yet, but wanted to get an idea of the difficulty level. Is there anything that needs to be torqued, or any special tools involved?

If anyone has any info or a thread to point me to I would appreciate it. This is one of those things I have never had occassion to do in the past.

Thanks for your time.

Regards,

Norm

[FordNut]

The rear universal joint/flange is attached to the yoke with 12-point bolts. They are installed with an air wrench and locktite. I couldn't break mine loose with hand tools so I had it done at the dealer.

[RF Overlord]

It IS possible to get them loose by putting the closed side of a combination wrench on the end of your socket wrench, making a sort of extended handle...I'm not sure how to describe it better...once you get the bolts loose, it's an easy swap...just remember to put a little light grease or transmission fluid on the new yoke before you slide it into the output shaft. Use red Loctite on the bolts and tighten to 84 ft-lbs...using a wobble on your socket will make tightening the bolts much easier.

[valleyman]

I'd never done a driveshaft removal before either, Norm and it wasn't that big of a deal. The four flange bolts DO have to be torqued and a wobble extension was a lifesaver for me, too. I honestly don't remember which wrench I used to get the flange bolts off, whether it was a socket or a closed end wrench, but I do remember that it was a mofo to break them loose -- due mostly to the factory installed red locktite. Putting them back on is not nearly as difficult as getting them off.

I had similar questions when I did mine. There's a thread started by me on 10/12/03 called "Metal Matrix Driveshaft Question," done when these things were much fresher in my mind.

Good luck.

[Svashtar]

Thanks a lot Valleyman! I'll check it out. I have a couple of breaker bars that should be able to crank them off if I can get enough room to work.

Regards,

Norm

[CRUZTAKER]

Changing out the shaft is no more difficult than changing a wheel....that's friggin rusted to the axle....:rolleyes: :D

Once the bolts are out it's really nthing more that pulling it out. You can DO IT!

[Bonedriver]

I did this recently to my Crown Vic.
Once you get the rear end up in the air, have a friend sit in the car and get him to set the e-brake and take the car out of park. Then you can turn the shaft at will and lock it down to start getting the bolts out. Once the pinion flange bolts are off (I used a 12mm 12pt impact socket and 1/2 inch impact gun - and it still took a long time to get the bolts to break free) I had to use a dead blow hammer to loosen the yoke from the flange as it was rusted together. With that off, the driveshaft's slip yoke will simply pull out of the tailshaft housing.
When you get everything ready to go back in (I recommend getting new bolts - it's less than $10.00 from the dealer) torque the bolts to 70-75 foot/lbs. I had very much a learning experience with my shaft installation as you will find out in the thread link below. It turned out to be rather simple in the end and a little bit embarassing. There are other driveshaft links at that site as well that might help you out. Also check out http://www.****zot.com/shaft.htm

http://www.crownvic.us/forum/showthread.php?t=6941&highlight=driveshaft

[Svashtar]

OK, thanks very much, however, I should have it easier than you did correct? I mean, it should just be a 1 for 1 swap, and I should not have to buy this tailshaft housing extension unit, is that right? Also, I don't believe I need to have the new shaft balanced. (?)

I'll lay the stock MM aluminium drivehaft next to the new MMX driveshaft I got from Dennis and measure them to make sure they are the same length, etc., but hope it will be just plug n' play. I'll call my dealer and ask if they usually swap the bolts out, but as the bolts are brand new with just about 1500 miles on the car, I had planned on reusing them after recoating with red loctite and then torquing them to 84 pounds as suggested by others here.

Thanks to everyone for all your helpful advice!

Norm

[cyclopsram]

Please use new bolts and torque them correctly.. The bolts stretch, just like the head bolts. The 80 lbft is a really high value for a little bolt like that... Be sure to use a new nut if you ever change out the front hub bearings too.... RAM :)

[BillyGman]

Please use new bolts and torque them correctly.. The bolts stretch, just like the head bolts. The 80 lbft is a really high value for a little bolt like that... Be sure to use a new nut if you ever change out the front hub bearings too.... RAM :)
I know that you're concerned about peoples' safety, and that's a good thing, and I can appreciate that. But just to let you know, there isn't a need to use new bolts on the driveshafts of cars that are merely a year or two old. There's nothing wrong w/torqing a bolt a second or third time. Infact some professional builders of racing engines actually torque the connecting rod cap bolts up to 5 times over during a build of exotic racing engines because that seasons the bolt.And keep in mind that the connecting rod cap bolts are the most critical fastener in the entire engine because they have to endure the greatest stress of any bolt in the engine. I for one really appreciate your post though, since I realize that you've written out of concern for your fellow Marauder owners. And that's really Cool.... ;)

[valleyman]

OK, thanks very much, however, I should have it easier than you did correct? I mean, it should just be a 1 for 1 swap, and I should not have to buy this tailshaft housing extension unit, is that right? Also, I don't believe I need to have the new shaft balanced. (?)

I'll lay the stock MM aluminium drivehaft next to the new MMX driveshaft I got from Dennis and measure them to make sure they are the same length, etc., but hope it will be just plug n' play. I'll call my dealer and ask if they usually swap the bolts out, but as the bolts are brand new with just about 1500 miles on the car, I had planned on reusing them after recoating with red loctite and then torquing them to 84 pounds as suggested by others here.

Thanks to everyone for all your helpful advice!

Norm

Norm, you don't need to have the MMX driveshaft balanced and you don't need to do anything except pull out the old OEM one and plug in the new one.

[David Morton]

Norm, you don't need to have the MMX driveshaft balanced and you don't need to do anything except pull out the old OEM one and plug in the new one.He's right on this, Norm, and one caveat from an ASE Master Tech, make sure you don't hit the pinion flange with any kind of hammer! It might bend and give you a vibration. Whack the old driveshaft ahead of the u-joint away from the pinion flange to break it free. And use Loctite blue on the old bolts.

[valleyman]

He's right on this, Norm, and one caveat from an ASE Master Tech, make sure you don't hit the pinion flange with any kind of hammer! It might bend and give you a vibration. Whack the old driveshaft ahead of the u-joint away from the pinion flange to break it free. And use Loctite blue on the old bolts.

Norm, just so you know, my MM had about 6K on it it I changed out my driveshaft, and like yours, mine has only experienced Central California weather so the driveshaft probably will separate from the pinion flange with no problem at all once you unbolt it.

And David Morton, red Loctite or blue Loctite? I used red since I figured I wouldn't be dealing with those particular threaded fasteners too often.

[David Morton]

And David Morton, red Loctite or blue Loctite? I used red since I figured I wouldn't be dealing with those particular threaded fasteners too often.
Yeah, that's ok but if you got blue, don't waste money buying red. Blue does fine in this application. Red is supposed to be for high-temp apps. but if you've already got it, use it. It is a bytch coming off though.

I agree the thing will probably pry off but somebody said he whacked his off with a deadblow hammer and in General Motors' vibration diagnosis and repair school that's a big no-no. There's a J-Tool specifically designed to pull flanges off pinions and they said to look for hammer marks on flanges and if you see any, get a new flange. I know a dead-blow plastic hammer won't mark the flange, but even a small bend in the flange will do amazing things to the driveline at say, 140 mph. Sorta defeats the purpose of the shaft.

That was a good school and I was especially pleased to get my new Marauder up to 115 mph and find it was as smooth as glass. :beatnik:

[Bonedriver]

Maybe I should've mentioned that I already had laying in wait was a new pinion flange yoke and pinion flange... so any whacking I did was purely for stress relief and was very enjoyable. :P

When I decided to upgrade my car I just went the route of purchasing new parts and not even worrying about using the old parts - that is except the driveshaft which needed the rebalancing after the new slip yoke, pinion flange yoke and Neapco U-joints. Just to quieten that voice in the back of your mind nagging you about "what if..."