mark 8 drive shaft compatability

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i have an 89' AOD thunderbird sc, i've found a 93 mark 8 1 piece alum. drive shaft. if i change the yoke will it be compatable with my setup? i understand there is a 7/8" difference in length, will i still have enough spline depth for it to be usefull?

Simon
 
what will leak? the yoke seal? any help anyone? there is only one i can find in b.c. right now so i want to grab it if i can...
 
Id say nogo....It fits my v8 car however just fine!,

You can look for a mercury marauder or polic epackage crown vic,,Get the shaft and shorten it
 
Id say nogo....It fits my v8 car however just fine!,

You can look for a mercury marauder or polic epackage crown vic,,Get the shaft and shorten it

I know this doesn't sound right, but the crown vic driveshaft would be too short for the aod.

Here's a handy little chart someone posted awhile back:


AOD, T5, and M5R2 all share the same 28 spline yoke. Easy swap to the new driveshaft. C/L Yoke to C/L yoke.

94-97 3.8L 4R70W 57" driveshaft (4R70W overall length 32")
89-95 3.8L M5R2 53.80" driveshaft (M5R2 overall length 35")
89-93 3.8L AOD 57.80" driveshaft (AOD overall length 31")
94-97 4.6L 4R70W 58.20" driveshaft (4R70W overall length 32")
93-98 Mark VIII 4R70W 58.20" driveshaft (4R70W overall length 32")
94-04 Crown Vic 4R70W 55.50" driveshaft (4R70W overall length 32")
 
rzimmerl, did you just change the yoke then? glad i checked this morn before i cancelled it coming up on the bus. i want it!
 
yep just swapped on the AOD yoke, and some new u-joints. I did have to loosen the rear end to drop it down some, as the flange wouldn't clear the pinion nut.
 
It's not a good idea to put a driveshaft in that doesnt have enough clearence. You may be looking for trouble in the future with that.

And I have a driveshaft that was from a marauder and its longer then my old auto driveshaft. Although now I'm wondering if thats my old auto driveshaft or one from one of my other cars..Hmmmmm

The 93 shaft from a mark viii fit my 95 lx v8 bird however no problems

WHat I would worry about is that the damage this may cause may not be seen for awhile. I'd like to hear from someone with allot of miles and a few years on theirs and who has inspected both the yoke of the driveshaft and the transmission. To me it just wouldnt be worth it
 
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It's not a good idea to put a driveshaft in that doesnt have enough clearence. You may be looking for trouble in the future with that.

And I have a driveshaft that was from a marauder and its longer then my old auto driveshaft. Although now I'm wondering if thats my old auto driveshaft or one from one of my other cars..Hmmmmm

The 93 shaft from a mark viii fit my 95 lx v8 bird however no problems

WHat I would worry about is that the damage this may cause may not be seen for awhile. I'd like to hear from someone with allot of miles and a few years on theirs and who has inspected both the yoke of the driveshaft and the transmission. To me it just wouldnt be worth it

I'm not sure I follow why you would have a problem with it---there is about a half inch or more of "play " in the shaft when its in place and the differential doesn't move a bunch..we have good mounts on both the engine and transmission so I'm comfortable with it until someone reports a problem.
Anthony has made several low 12 second passes on it on slicks as well as street driving. We are shooting for some 11 second passes this year---stay tuned, if a problem developes we will spread the word..........Dan
 
Remember that this setup with the play was designed for a regular rear end not a IRS.

I would think that on a IRS car that yolk would barely move.
 
My question is why do it.....:confused:

If its for weight savings, it just isn't there.....

Both drive shafts weigh approximately the same.....
 
My question is why do it.....:confused:

If its for weight savings, it just isn't there.....

Both drive shafts weigh approximately the same.....


The one piece 1993 Aluminum shaft weighs a bit less, 14 pounds versus 19 pounds for the steel shaft.

The Two piece aluminum shafts are almost as heavy as the steel shaft.

- Dan
 
Well .4 is definitely better then the full inch as mentioned. And yes the IRS is for the most part stationary. As for our engine or tranny mounts being good and not causing excessive movement, I dont know about that one, or even if there were to be an issue with the IRS mounts.

I'm sure however .4" could easily be machined of the yoke. Afterall being its .4 inches in more you are still getting the proper spline engagement which wouldnt be an issue.
 
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