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Got a 351 for sketchy, and I want to have two powerplants i can bolt in and out on a whim. A tame street 302 that it's already got, and a no compromises 351.
It's my understanding that the M5R2 five speed and the AOD have the same overall dimensions, at least within slip yoke tolerance, which appears to be confirmed with this image, at least.
So theoretically, I can simply swap in the motor and trans as one unit while modifying nothing else. However I can't find any information on the yoke/output shaft splines. I have a really nice driveshaft made with big power in mind, and it'd suck to have to pay another 500 bucks for another just to play nice with the AOD.
Does anyone have an AOD/yoke to compare spline counts? Or does this perhaps vary from year to year, so I have to hunt a specific era of trans?
While i'm on the topic, what about TQ's and flexplates? The 351 i pulled has an E4OD attatched to it, and I'm not sure if it's a 155 or 163 tooth flexplate, and I believe the AOD takes the 163. Likewise, if the flexplate will carry over, what are the odds the converter is compatable? I know nothing about automatics and I could use some advice here.
Make sure the flexplates are compatable . I destroyed a freshly rebuilt AOD by using the flexplate from my 351 - c6 donor . As it turns out everything bolts up just fine but the c6 flex has a different offset putting pressure on the front pump and very quickly ruining it . My AOD is out of a 1990 crown vic 302 so I can find the driveshaft and count the splines for you .
The other thing to know about the flexplates is that the 351 uses a 28oz imbalance where the 302 after 1980 used a 50oz. They cannot be interchanged, even if everything else matches. It creates a horrible vibration.
The yoke has 27 male splines and a blank master and is 1.5 inches od .
Looks like a match. Swell.
Originally Posted by EBEAR
Make sure the flexplates are compatable . I destroyed a freshly rebuilt AOD by using the flexplate from my 351 - c6 donor . As it turns out everything bolts up just fine but the c6 flex has a different offset putting pressure on the front pump and very quickly ruining it . My AOD is out of a 1990 crown vic 302 so I can find the driveshaft and count the splines for you .
Yeah, i really hope the E4's is compatable, flexplates and TQ's are expensive. Can't find much info though.
It's my understanding that the M5R2 five speed and the AOD have the same overall dimensions, at least within slip yoke tolerance, which appears to be confirmed with this image, at least.
Does anyone have an AOD/yoke to compare spline counts? Or does this perhaps vary from year to year, so I have to hunt a specific era of trans?
While i'm on the topic, what about TQ's and flexplates? The 351 i pulled has an E4OD attatched to it, and I'm not sure if it's a 155 or 163 tooth flexplate, and I believe the AOD takes the 163. Likewise, if the flexplate will carry over, what are the odds the converter is compatable? I know nothing about automatics and I could use some advice here.
Thanks.
The flywheel / flexplate tooth counts would be 157 and 164. Since the M5R2 and the E4OD are both truck transmissions, they'll both be 164 tooth. Since the AOD was in both trucks and cars, it could be either one...but if your AOD has a 1.5" slip yoke, then it should also be out of an F150, which means it should also be 164 tooth. Somebody can correct me if I'm wrong, but one quick way to tell a car AOD apart from a truck AOD is the larger output shaft, and thus larger slip yoke.
E4OD and AOD flexplates cannot be swapped however. C6 flexplate will match up with E4OD, and C4/C5 will match up with AOD.
302 was 28oz imbalance up to 1982, when it changed to 50oz. The 351w was always 28oz from beginning until the end in 1997 or so.
Another thing to be aware of is that the auto and manual starters cannot be swapped around. They are specific to each.
The flywheel / flexplate tooth counts would be 157 and 164. Since the M5R2 and the E4OD are both truck transmissions, they'll both be 164 tooth. Since the AOD was in both trucks and cars, it could be either one...but if your AOD has a 1.5" slip yoke, then it should also be out of an F150, which means it should also be 164 tooth. Somebody can correct me if I'm wrong, but one quick way to tell a car AOD apart from a truck AOD is the larger output shaft, and thus larger slip yoke.
E4OD and AOD flexplates cannot be swapped however. C6 flexplate will match up with E4OD, and C4/C5 will match up with AOD.
302 was 28oz imbalance up to 1982, when it changed to 50oz. The 351w was always 28oz from beginning until the end in 1997 or so.
Another thing to be aware of is that the auto and manual starters cannot be swapped around. They are specific to each.
Originally Posted by Conanski
They are not, both the flexplate and torque converter are unique to the AOD.
Useful info, thanks.
Guess i'll see if the local parts yard will take the complete E4 as trade against a truck AOD
I have a 89 f150 2x4 and I am looking for a new M5R2 slip yoke for my transmission. They don't appear to be sold any more. So if I understand this correctly that a AOD slip yoke will fit in a M5R2 Mazda transmission?
