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Triumph TR6 - J type OD.. PLS help!?!

I engaged the OD once on the highway and all appeared fine: drop in RPM, smooth operation. After an hour highway driving, I switched off the OD when pulling off to get gas but there was no change in RPM. Out of the gas station, I switched it on and again, nothing. I can't tell if its stuck on or if its not engaged at all. Its reading 2500 rpm at 50 mph in 3rd and 2500 rpm at 70 mph in 4th. The solenoid sounds like its moving.

Can anyone help here?

These are my questions:
At the given rpms and speed, is the OD on or off?
Is there a test I can do in situ?
Will the pump pressure ease when the car is stopped to the point where the OD will disengage?
Can I reverse?
Is it time for a mechanic?

Again, any suggestions would be greatly appreciated.

B Chamberlain

Sounds like it is stuck on if you are getting 2500 rpm at 70 mph. Engagement lever may be jammed or stuck so it may not be disengaing when you turn off the solenoid.

You will have to inpect it Bryn
Michael Petryschuk

I have about 2 pages of troubleshooting "J" type overdrives. Send me your E mail address or I can post it here if there is no rule on posting things like this ( takes up lots of space )


Mitch Smith

Saw this post in your other thread and responded there.

Tom Sotomayor

OD Update: Today, its fine. I took the cover off and ran it through the gears with the drive shaft disconnected: all clear. As Tom has indicated, it may have been the new cone clutch stuck om a high spot (it was also a VERY hot day on the 401 highway).

whew! Great relief. I wonder if these things are susceptible to higher operating temps?

Thanks again to all. BBS rocks. What an great resource.
B Chamberlain

Bryn, you should have mail. if anyone else would like some J type OD trouble shooting, let me know and i can E mail it to you so as not to clutter up bandwidth here.


Mitch Smith


I had a solenoid stick in the on position in my 74 J Type OD. I had to take it apart an hone out the plunger. It can happen; and you do not want to drive in reverse with the OD engaged

John Korsak

This thread was discussed between 10/08/2007 and 13/08/2007

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