High RPM Vibration After Tremec 3550 Swap

Discussion in 'Drivetrain' started by 94mustangsvt, Aug 8, 2016.

  1. 94mustangsvt

    94mustangsvt New Member

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    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.
     
  2. lwarrior1016

    lwarrior1016 Moderator Staff SN95 Supporter

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

    Does it have alignment dowels, and is the trans straight with the engine?
     
  3. 94mustangsvt

    94mustangsvt New Member

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    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.
     
  4. Nighttrain

    Nighttrain Well-Known Member

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    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.
     
  5. 94mustangsvt

    94mustangsvt New Member

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    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?
     
  6. Nighttrain

    Nighttrain Well-Known Member

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    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.
     
  7. 94mustangsvt

    94mustangsvt New Member

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

    Nighttrain Well-Known Member

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

    Nighttrain Well-Known Member

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    Or order one custom made, the driveshaft shop is probably most popular.
     
  10. mcglsr2

    mcglsr2 Well-Known Member SN95 Supporter

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    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).
     
  11. lwarrior1016

    lwarrior1016 Moderator Staff SN95 Supporter

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

    Nighttrain Well-Known Member

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    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
     
  13. 07GtS197

    07GtS197 Well-Known Member

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    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.
     
  14. mcglsr2

    mcglsr2 Well-Known Member SN95 Supporter

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    Yah, my 95 is a 50 oz...
     
  15. Nighttrain

    Nighttrain Well-Known Member

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    Ok.....sorry backwards
     
  16. white95

    white95 Apex Junky Admin

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    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

    Stanget