Driveshaft Options

[Big House]

Greetings,

I have been looking across the great WWW for a replacement for my driveshaft. I am getting the 90mph shakes since installing the 4:10's so it is time. I just don't have $525 bones to shell out. I have read about the greatness of the MMx but the price is commanding. For those on the lookout for a better than stock driveshaft, I am looking into Driveshaft Speciaists on Texas. Their top of the line shaft complete with tranny yoke lists for $315-$345 depending on DS length. By the way...what is the Center to center length of our drive shafts. That will help me lock in the pruchase. Thanks

House

[Marauder386]

I would suggest looking in your area for a junkyard that takes in older P71's...Do some research and find a driveshaft from one of them, take it to a reputable shop to have it cleaned up, balanced out and installed. Quite a few of the CVPI's had or have a MMC (?) or MMX ( ? ) on them indicating a lighter stronger shaft. Just my 2 cents....


:coolman:

[rayjay]

Will having the OEM drive shaft balanced work?

[03MERCMARAUDER]

Nice info, I didnt know that

Joe

[StevenJ]

Is your car an A model or a B model 03? Just curious. I'm thinking of doing the gears in time as well.

[Marauder386]

RayJay, I really dont know Bud...it is worth a try...experiment ?
03Merc...trying to come from the angle of saving cash....for future mods !
:coolman:

[Tallboy]

Will having the OEM drive shaft balanced work?

This would be the first thing I'd do.

For about $40, Driveshaft Specialists will balance it and tell you if the balance was "off".

[MM2004]

Greetings,

I have been looking across the great WWW for a replacement for my driveshaft. I am getting the 90mph shakes since installing the 4:10's so it is time. I just don't have $525 bones to shell out. I have read about the greatness of the MMx but the price is commanding. For those on the lookout for a better than stock driveshaft, I am looking into Driveshaft Speciaists on Texas. Their top of the line shaft complete with tranny yoke lists for $315-$345 depending on DS length. By the way...what is the Center to center length of our drive shafts. That will help me lock in the pruchase. Thanks

House

House,

Did the car vibrate prior to the gear install?

Mike.

[SergntMac]

Tallboy's right. Check the balance first, may have lost a weight.

The dirve shaft issue is not a matter of balance in the typical use of the word. It's driveshaft "whip" where the rotational speed exceeds a predetermined limit of the material used to construct the driveshaft. This is why it gets corrected by the MMC (metal matrix composite) shaft. Different blend of aluminum, different rotational limitation. It will still whip, but at higher speed, hopefully speeds you do not travel at.

[Big House]

Mike,

I have seen 115-120 before the gear swap and no shakes...Just like previous cars, this was the case. I did a swap in my T-bird and the same thing happened. I pegged the neddle in my T-bird before the swap...in excess of 130 and no shakes...after the swap and ashaft balance...no more than 90. This is why I am leaning towards getting a shaft made to take the speed and revolutions.

House

[hitchhiker]

Tallboy's right. Check the balance first, may have lost a weight.

The dirve shaft issue is not a matter of balance in the typical use of the word. It's driveshaft "whip" where the rotational speed exceeds a predetermined limit of the material used to construct the driveshaft. This is why it gets corrected by the MMC (metal matrix composite) shaft. Different blend of aluminum, different rotational limitation. It will still whip, but at higher speed, hopefully speeds you do not travel at.

X-Act-Ly!

The Sarge is right.

The whip on the OEM Drive shaft (03/04 MM) is causing this vibration. It will eventually wear the rear seal of the tranny.

The older CVPI's with the lower gears had an AMMX driveshaft which will do quite nicely in our MM's. May need the old yoke too; I don't remember.

Regards,

David

[SergntMac]

If you track the evolution of the CV/PI drive shaft through history, you'll discover that we already have it in the Marauder.

FMC first discovered this whip point and subsequent vibration after offering a 3:55 gear option in the CV/PI. Changing gears from 3:23 to 3:55 brought the whip point down closer to speeds the vehicle was being used at. Blow enough tranny and rear end seals, you'll complain and cops complained.

FMC developed the MMX police shaft to repair that by using another material in production, and pushed the whip point back up the RPM/MPH scale. Later, they added the MMX shaft to the production line.

Our problem is that we have repeated history. If we would leave well enough alone with the 3:55 gears, no one would be bothered. But, we change them out for higher ratios, thus pulling the whip point back down to where we drive the car.

Not every drive shaft will exhibit this whip, but if it's going to show up, it will be after a gear change to 4:10s or taller gears. Don't buy nothing until you need too. Just my .02C, carry on gents.

[RF Overlord]

rayjay, you can TRY getting your stock DS balanced, but, as Mac and hitchhiker said, it probably won't do any good as it's not a "balance" problem...check out this (http://www.mercurymarauder.net/forums/showthread.php?t=5163) thread for a really nice explanation of Driveline Critical Speed.

[CRUZTAKER]

I would suggest looking in your area for a junkyard that takes in older P71's...Do some research and find a driveshaft from one of them, take it to a reputable shop to have it cleaned up, balanced out and installed. Quite a few of the CVPI's had or have a MMC (?) or MMX ( ? ) on them indicating a lighter stronger shaft. Just my 2 cents....




I got lucky and got two of the last OEM NEW (MMC-POLICE) Metal Matrix Comp Dynotech driveshafts (XW7Z-4602-AA) before they went bye-bye forever. $180:coolman:

Last new ones were gone in early 2005.

I don't care what anyone says. I have been well over the 'well over the limit' triple digits many, many, many times without any resonating.

[DEFYANT]

This DS wooble you all are talkin about... how come I never felt it? I have the 4:10s and have been well over 100 mph, at the track of course, and never had this problem.

[FordNut]

Some do it, some don't. Variances in mass production manufacturing processes. If you don't have it you got lucky.

Step-by-step fixes...
1. Try re-balancing the OEM shaft. Some have had success. Cost about $50-$100.
2. Try to find an older CVPI shaft from a junkyard. Maybe even have it rebalanced. Maybe it'll work. Cost unknown.
3. Buy a dynotech MMX shaft. Problem fixed for around $500-$550
4. Buy a carbon fiber shaft. Problem fixed for $800-$900

Take your pick, but #1 and #2 might not work, if not it's $$$ down the drain.

[Marauder386]

See..I was in the ballpark...just tryin to save the man some cash to put other places...:D

:coolman:



I got lucky and got two of the last OEM NEW (MMC-POLICE) Metal Matrix Comp Dynotech driveshafts (XW7Z-4602-AA) before they went bye-bye forever. $180:coolman:

Last new ones were gone in early 2005.

I don't care what anyone says. I have been well over the 'well over the limit' triple digits many, many, many times without any resonating.

[BigCars4Ever]

The P71 years you would be looking for are mid 1999 to early 2000. If the DS is still in the car a 3:55 axel tag will ensure the car is AMMX equipped. Some searching on crownvic.net will yield more info on id'ing the correct shaft.

[CRUZTAKER]

Correct.

I have pics at home I can post later if you like.

Appearence wise, it has the came colored bands as ours. But at one end it will have an engraving on it. The ones I had were engraved via stamped ink.

"MMC POLICE"

[Big House]

Cruzer,

Thanks alot fo the look out. I think at the most I will be out $400 for a 1350 series shaft balanced with the tranny yoke. I have a rough length but I an going to get her up on a lift today and get more accurate measurements. Thanks ya'll.

House

[SergntMac]

Cruzer,

Thanks alot fo the look out. I think at the most I will be out $400 for a 1350 series shaft balanced with the tranny yoke. I have a rough length but I an going to get her up on a lift today and get more accurate measurements. Thanks ya'll. House Remember some other considerations...

The DynoTech MMC shaft was last priced at 525.00 delivered to your door. A group buy may lower that, if you can get one started.

The DynoTech MMC shaft is an assembly, with fresh yoke, fresh rear flange and beefy Dana 60 universal joints, all balanced and ready for install.

IMHO, by the time you piece together your idea, you may spend more.

Just my .02C, good luck with your project.

[gdmjoe]

CRUZTAKER - Correct. I have pics at home I can post later if you like. Appearence wise, it has the came colored bands as ours. But at one end it will have an engraving on it. The ones I had were engraved via stamped ink. "MMC POLICE"
Not meaning to step all over your offer CRUZTAKER, but here's some 411 (http://www.****zot.com/shaft.htm) <<<<< -click-

*And attachments.

[SergntMac]

Interesting article, Joe. Maybe House ought to check and see if his driveshaft went back in correctly indexed?

[Zack]

This DS wooble you all are talkin about... how come I never felt it? I have the 4:10s and have been well over 100 mph, at the track of course, and never had this problem.


You wont feel it, thats the thing!
When your tailshaft seal pulls out, then you will feel it.

[MM2004]

Remove the driveshaft and rotate it 90 degrees CC or CCW and bolt back in and take her back out for a high speed pass.

You may need to repeat this process a few times to possibly eliminate the vibration.

Your gears were changed as well as the pinion TIR.

Re-orienting the driveshaft may very well line up the light side imbalance of the driveshaft with the high side of the pinion TIR.

Could save some $$$.

If the vibration goes away, go to your L/M Dealer and get new bolts. It is not recommended re-using bolts for the driveshaft.

Post # 4 for specs.

http://www.mercurymarauder.net/forums/showthread.php?t=17674&highlight=driveshaft+specs

Mike.

[FordNut]

You wont feel it, thats the thing!
When your tailshaft seal pulls out, then you will feel it.
Exactly my experience. Caught it before the seal pushed out, but it was leaking. Couldn't actually feel any vibration though.

[SergntMac]

Post # 4 for specs.

http://www.mercurymarauder.net/forums/showthread.php?t=17674&highlight=driveshaft+specs Mike. Mike is being shy, but trust me here. He knows more about all this drive shaft stuff that we know about him. Mike can fill in the details where he wants...

BTW, Thanks, Mike!

[merc6]

so whats the difrence in the police one with extention vs the one on DR site. I'm refering to price vs function.

[Big House]

MM2004,

By rotate, do you mean completely remove the DS or just remove the bolts from the rear flange, leave the tranny in neutral and twist her around. If this is what you mean I will do that first.

House

[CRUZTAKER]

Not meaning to step all over your offer CRUZTAKER, but here's some 411 (http://www.****zot.com/shaft.htm) <<<<< -click-

*And attachments.

The sentence that I was unaware of reads...
"...The MMC shaft must also be installed with the longer tailshaft extension housing in order to properly support it."

The material in that link directly applied to folks upgrading their Crown Vics.

Is the Tranny tailshaft in the Marauder the same as the crown vic....is the tranny even the same?

I'd like to know that sooner than later...because I have put nearly 27k miles on the DS. :dunno:

[MM2004]

MM2004,

By rotate, do you mean completely remove the DS or just remove the bolts from the rear flange, leave the tranny in neutral and twist her around. If this is what you mean I will do that first.

House

Bingo! As you said here -> remove the bolts from the rear flange, leave the tranny in neutral and twist her around. If this is what you mean I will do that first.

If you are in need of more assistance, PM me your number and I will call you.

Good Luck,

Mike.

PS. Thanks Mac. :o

[DEFYANT]

You wont feel it, thats the thing!
When your tailshaft seal pulls out, then you will feel it.

Alright! I've heard this before. I believe you. I need to make a phone call to my DS shop.

Yo, Any venders out there wanna do a group purchase? :help:

[gdmjoe]

CRUZTAKER - The sentence that I was unaware of reads...
"...The MMC shaft must also be installed with the longer tailshaft extension housing in order to properly support it."

The material in that link directly applied to folks upgrading their Crown Vics.

Is the Tranny tailshaft in the Marauder the same as the crown vic....is the tranny even the same?

I'd like to know that sooner than later...because I have put nearly 27k miles on the DS. :dunno:
Do know that when I upgraded my 2003 LX Sport with the FoMoCo MMC driveshaft that the extended tailshaft housing was required. Can't speak to matter of the Marauder's tailshaft housing. *Could crawl up under there and see if it's F5UZ-7A039-A (the extended version).

As a BTW ... The speed sensor plug for the extended housing is F2UZ-7H183-A and the gasket is F7AZ-7086-A.

[SergntMac]

Do know that when I upgraded my 2003 LX Sport with the FoMoCo MMC driveshaft that the extended tailshaft housing was required. Can't speak to matter of the Marauder's tailshaft housing. *Could crawl up under there and see if it's F5UZ-7A039-A (the extended version). As a BTW ... The speed sensor plug for the extended housing is F2UZ-7H183-A and the gasket is F7AZ-7086-A. Thanks, Joe, these are indeed the correct part numbers for the 4R70(75)W tranny tailshaft in the Marauder. Folks, if you own a Marauder, these parts are in place, I know because I replaced them to install the forced tailshaft lube kit for improved lubrication of the tailshaft bearing and seal.

Why a 2003 CV LX Sport has a shorter tailshaft, I can't say, but I'll make a guess? Engine placement?

The DOHC 4V in the Marauder sits further forward in the engine bay so the 4V heads will clear the firewall. The SHOC 2V in the CV sits further back because it has clearance the 4V does not have. Therefore, a shorter tailshaft housing for the CV, and a longer housing for the MM.

Good guess?

[gdmjoe]

SergntMac ... Why a 2003 CV LX Sport has a shorter tailshaft, I can't say, but I'll make a guess? Engine placement?

The DOHC 4V in the Marauder sits further forward in the engine bay so the 4V heads will clear the firewall. The SHOC 2V in the CV sits further back because it has clearance the 4V does not have. Therefore, a shorter tailshaft housing for the CV, and a longer housing for the MM.

Good guess?
Nope (not a good guess, bud') :D

It must be one of those mysteries of life 'cause the P71s (police) have the extended tailshaft housing as stock with the aluminum driveshafts.

I surmise that it has something to do with the length of the driveshafts ... the more performance (and supposedly higher MPH / RPM) the shorter the driveshaft.

*It's that harmonic balance, cosmos factor.

[SergntMac]

Ummm...Oh well, it was worth a shot.

[BigCars4Ever]

Why a 2003 CV LX Sport has a shorter tailshaft, I can't say, but I'll make a guess? Engine placement?


Only the P71's had the extended tailshaft. The p73 74 and 75 had steel driveshafts and were governed to well bellow the CS of the shaft. Since the P71's were governed to 130's and came with 3.27 or 3.55 they required the shorter aluminum DS like ours or the AMMX like the 99 - 00 P71's. This was all an afterthought on Ford's behalf and was implemented in the mid/late 90's.

[MM2004]

Not meaning to step all over your offer CRUZTAKER, but here's some 411 (http://www.****zot.com/shaft.htm) <<<<< -click-

*And attachments.

A word of caution in comparing the two driveshafts as shown in the link while referencing our MM's.

One driveshaft is steel (rust) while the other is aluminum.

The steel shaft has a "damper" that is pressed onto the trans. yoke (obvious NVH correction technique).

Tube lengths are different as are the tube yokes.
However, the overall lengths appear similar to one-another.

The trans. yoke splines are machined differently (chamfered/recessed).

Just my :twocents: .

Mike.

[sabtaj1]

I am planning on putting 4.10s in my 03 m/m next week. I also have a 99p-71 that I am trying to sell. So would it be worth it to swap out the driveshafts before I sell the p-71? any input would be great. Jason

[Rider90]

I am planning on putting 4.10s in my 03 m/m next week. I also have a 99p-71 that I am trying to sell. So would it be worth it to swap out the driveshafts before I sell the p-71? any input would be great. Jason
Another Jason on this board from IL? Isn't that the third? That's it! I'm changing to Fred Flintstone.

[BigCars4Ever]

I am planning on putting 4.10s in my 03 m/m next week. I also have a 99p-71 that I am trying to sell. So would it be worth it to swap out the driveshafts before I sell the p-71? any input would be great. Jason

Jason, Not all 99's have an ammx driveshaft. Check your shaft before you pull it out. If it is stamped POLICE AMMX then I'd swap it before selling the p71.