High RPM Vibration After Tremec 3550 Swap

[94mustangsvt]

I recently swapped out the T5 in my 94 Cobra for a used Tremec 3550. It only has about 200 miles on it since the swap. It now has vibration above 3,000 RPM that seems to get worse the higher you go. It doesn't seem to do it in neutral.

I installed a resurfaced flywheel with all three dowels and a new Spec Stage 2 clutch. It also has new pilot and throwout bearings. After installing a slightly taller stock transmission mount and a spacer, the issue seems somewhat better, but still there.

I know the pinon angle is still off because it starts vibrating pretty bad at around 70-75 mph, but this seems like a different issue.

Could something be wrong with the clutch or flywheel? Transmission angle? Maybe a bent input shaft or mainshaft in the transmission?

Any input is appreciated, thank you.

 

[lwarrior1016]

I recently swapped out the T5 in my 94 Cobra for a used Tremec 3550. It only has about 200 miles on it since the swap. It now has vibration above 3,000 RPM that seems to get worse the higher you go. It doesn't seem to do it in neutral.

I installed a resurfaced flywheel with all three dowels and a new Spec Stage 2 clutch. It also has new pilot and throwout bearings. After installing a slightly taller stock transmission mount and a spacer, the issue seems somewhat better, but still there.

I know the pinon angle is still off because it starts vibrating pretty bad at around 70-75 mph, but this seems like a different issue.

Could something be wrong with the clutch or flywheel? Transmission angle? Maybe a bent input shaft or mainshaft in the transmission?

Any input is appreciated, thank you.

What did you use to adapt the 3550 to the pushrod?

Does it have alignment dowels, and is the trans straight with the engine?

 

[94mustangsvt]

The 3550 is the predecessor to the TKO so it just uses a TKO aluminum bellhousing for a sbf. The engine still has the alignment dowels. I didn't check the run-out on the bellhousing so maybe it needs offset dowels?

It looked pretty straight, but maybe I should get it back up on my parents' lift when I get a chance to make sure.

 

[Nighttrain]

Did you have to change driveshaft length? Did you have it ballanced after? What throw out bearing brand did you use? Oem ford or nothing, my opinion anyway.

 

[94mustangsvt]

Did you have to change driveshaft length? Did you have it ballanced after? What throw out bearing brand did you use? Oem ford or nothing, my opinion anyway.

The Spec clutch came with new pilot and throwout bearings so I used those. I used the same driveshaft with a spacer, could that be the problem?

 

[Nighttrain]

If its not balanced yes, most aftermarket throwout and pilot bearings are junk including frpp. Oem is the best out there. Any time you make changes to the driveshaft even a spacer (which i personally wouldnt recommend) it needs to be balanced.

 

[94mustangsvt]

If its not balanced yes, most aftermarket throwout and pilot bearings are junk including frpp. Oem is the best out there. Any time you make changes to the driveshaft even a spacer (which i personally wouldnt recommend) it needs to be balanced.

Would you recommend just getting the current aluminum driveshaft lengthened and balanced then?

 

[Nighttrain]

There are shops out there that do it. Being in cali your in a good spot for a good shop.

 

[Nighttrain]

There are shops out there that do it. Being in cali your in a good spot for a good shop.

Or order one custom made, the driveshaft shop is probably most popular.

 

[mcglsr2]

Yah my guess is it's the driveshaft (and possibly pinion angle), assuming the flywheel is the proper balance.

Edit: and just to ask, the flywheel is the proper balance for the engine, yes? There are two options, the 50oz and 28oz (I think).

 

[lwarrior1016]

That driveshaft spacer is probably whats doing it. Would a driveshaft from a new edge fit?

 

[Nighttrain]

Yah my guess is it's the driveshaft (and possibly pinion angle), assuming the flywheel is the proper balance.

Edit: and just to ask, the flywheel is the proper balance for the engine, yes? There are two options, the 50oz and 28oz (I think).

I know he hasnt been back warrior but the 50oz flywheels were for 79 and older 302's right? Cant remember the year exactly but the 28oz should be the right one......i think

 

[07GtS197]

You have it backwards, the pre 81's were all 28 oz then ford switched to 50 oz.

Edit: Wow Im an idiot I wrote 28 twice lol. Fixed.

 

[mcglsr2]

Yah, my 95 is a 50 oz...

 

[Nighttrain]

Ok.....sorry backwards

 

[white95]

OK, you guys listen up! You have to either run a Stifflers transmission crossmember -or- [cheaper option] flip the oem crossmember around to allow the 3550 to sit correctly in the trans tunnel. Why? It'll vibrate it ass off because its canted to the passenger side. How do I know this? Experience!! In my thread, someone mentioned a guys vibrations came back but it never did in my car.

parts used:

Tremec TR3550
FRPP Tremec bellhousing
fox clutch fork
FRPP aluminum driveshaft
Energy Suspension trans. mount
Pro 5.0 shifter


My thread on this topic from 2008

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