rearend shaking

[badmustang]

A 1 1/16" input shaft was used in motors from the 200 c.i. to the 390 c.i. while the 427, 428 and 429 used a large 1 3/8" input shaft. The 427, 428 and 429 were available only with close ratio gears. While the 1 1/16" input transmissions are available in both close and wide gear ratios.

 

[badmustang]

Normally all motors 200 c.i. - 390 c.i. use the 28 spline output shaft. All 427, 428 & 429 motors use the 31 spline output shaft. There are a few exceptions to the above information. The toploader was produced in 133 models.

 

[65FBE2]

I had the same shudder many years a go and found it to be the U bolts that hold the rearend to the spring plates. If you have added traction bars, this can happen slowly over time and you will chase your tail looking for it in the drive line when in fact it may be the rear axle housing shuttering on the leaf springs

 

[RED2001GT]

Hey Jay, do they use any salt on the roads during the winter months when it snows up where you are at in Rotterdam? I was curious about whether or not your 69 Mustang has any rust on it from the salt that's used on the roads if they ever use salt on the roads when it snows up where you drive in Rotterdam?
Do you drive your 69 Mustang thruout the whole winter time?
What do drive besides the 69 Mustang that you own?

 

[badmustang]

Hey Jay, do they use any salt on the roads during the winter months when it snows up where you are at in Rotterdam? I was curious about whether or not your 69 Mustang has any rust on it from the salt that's used on the roads if they ever use salt on the roads when it snows up where you drive in Rotterdam?
Do you drive your 69 Mustang thruout the whole winter time?
What do drive besides the 69 Mustang that you own?

no i do drive only is the summer and spring the car is in the garage in winter.
sind i own the car it had never seen rain

 

[badmustang]

I had the same shudder many years a go and found it to be the U bolts that hold the rearend to the spring plates. If you have added traction bars, this can happen slowly over time and you will chase your tail looking for it in the drive line when in fact it may be the rear axle housing shuttering on the leaf springs

okee thanks will look also for that.. added traction bars but before that the car shudder. mabye the u bolts are not tight enough

 

[gunmetal5.0]

You should post a vid of a black womans big azz shaking for those that opened this thread thinking(Hoping) it was something else. *Sigh*

 

[dennis112]

Duplicate post

 

[dennis112]

okee thanks will look also for that.. added traction bars but before that the car shudder. mabye the u bolts are not tight enough

While there, check for cracked or broken spring perch (on the rear end.)

 

[dennis112]

Yes, it only takes an input shaft swap to create a SBF tranny, (disregarding the output shaft) but the input shaft must match the ratio of the tranny. There were only 2 ratios, a 2.32 close ratio and the 2.78 wide ratio. Easy to determine which ratio you have by counting the # of teeth on 2nd gear. You would have to do a visual to verify the BBF shaft. Don't ever rely on the production #'s found on the side of the case as all early toploader cases are identical short of that little metal ID tag.

Lots of 390's came with 4 speeds and they have the short input shaft, and yet the remainder of the tranny is the same as the SBF--28 spline output shaft. The clutch disc would be the same. The larger cube BBF would/should have the larger 31 spline output. You do not have to worry about that end since you already have a driveshaft hooked up.

As I said, it is a shot in the dark that this is your problem, but it seems like you have covered the normal items.

Another thought, you might want to take a dial indicator and check the run-out of the new flywheel as it is installed on the back of the crank. Not sure of the exact spec, but I would expect it to be something less than .010".

 

[badmustang]

how much play does the drive shaft have in the tailhousing...

i was unther the car and wiggel the drive shaft up and down (near the tailshaft) i could wiggel it a littel bit up and down but not side ways..

is that a problem or does the drive shaft not must have a wiggle..

sorry for my englisch (may be yo know what i mean)

 

[dennis112]

how much play does the drive shaft have in the tailhousing...

i was unther the car and wiggel the drive shaft up and down (near the tailshaft) i could wiggel it a littel bit up and down but not side ways..

is that a problem or does the drive shaft not must have a wiggle..

sorry for my englisch (may be yo know what i mean)

There will be a slight amount of wiggle as there needs to be a little play between the tailhousing bushing and the driveshaft yoke. It shouldn't be much though--ever so little. Another "possible" sign of a bad tail housing bushing is a transmission fluid leak at the rear seal.

If you think there is excess play, the bushing can be replaced. You would need to unbolt the tail housing in order to do it--not a major job except for the fluid mess and needing to remove the shifter. You should also check the condition of your yoke where it rides in the bushing. They are available too.

 

[66bluepony]

Shudder

Clutch Disc.