Transmission shudder when idle?

My 1975 Triumph 2500 automatic (Borg Warner type 35, three speed, no lock up) is misbehaving itself. The car shudders severely from about 40 mph onwards, you can feel the whole car shimmering. To try to solve this I did the following:

  • changed driveshafts for known good examples
  • changed propshaft
  • changed wheels & tyres (from a car without vibration)
  • changed flexplate
  • changed BW35 incl torque converter

The engine rubber mountings and rear gearbox rubber mounting are as new, no cracks or old-age signs.

After the gearbox change, it has become worse. It now even shudders when idling, more when increasing revs. The engine otherwise runs smooth on all 6 cylinders.

I am at a loss, don't know where to look now. It cannot be the drive line because of the shudder when stationary. Could it be that the Torque Convertor is playing up? The replacement is coming from a car which has been standing for several years.

Any tips and hints gratefully received.

Dion.

Reply to
150milesperday
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Do you feel the shudder when the car is running, but in park or neutral, or only when it is in drive?

Reply to
<HLS

you need to spin the tourque converter on the fly wheel until it smoth is out

it is out of balance . this make take some time until you find the right combination make sure you mark witch way you are going

Reply to
tudysmuck

You said *any tips....*so, might we be working on the wrong end of the engine? Dunno much about Triumphs, but I've surely seen a bunch of Fords where the harmonic balancer got out of balance when the inner part slipped inside the outer part--held together with a rubber-like cushion between the

2 circumferences. They too were worse at higher rpm's yet noticeable at idle as well. HTH & good luck. s
Reply to
sdlomi2

Did you clean the convertor before installing it? If it's been standing for some time, and had old fluid in it, then all the old crap from the trans is still in there...but that probably wouldn't cause your shudder.

How does the harmonic balancer on the other end of the crankshaft look?

because if you changed the trans, convertor, and flexplate, it stands to reason that it can't be in those components...and if the mounts are all good, probably can't be them... I'd check out that balancer...

-LMB

Reply to
Louis M. Brown

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