OD relay

ha; Any generic three or four terminal relay will do the job nicely...see article for options on wiring diagrams: Cheers

Russ; If you must have OD available in 3rd gear also, you would have to enable it with a switch in the same way it is enabled for 4th gear only (I expect this could essentially be accomplished with another strategically located switch on the gearbox cover)...both switches could be wired in parallel....but I frankly don't think it's needed...with the wide torqueband of our engines, combined with the gearing, it results in good overlap, so I just question how necessary it is to have 3rd/OD available. Cheers

thanks plus comment 

rk thanks for the info and web page. I did look up that particular question already and either didn't recognize the answer, electrics are my weak spot, or missed it entirely. Will look again. TDZ840 and RK My 62 sedan if fitted with an OD already and it doesn't seem to have a lock out incorporated as I seem to be able to shift into any gear while it is on w/o any detriment. I don't usually do this except by accident, because I have been told that it really isn't good for the trans or OD. How is the lock out supposed to work? And is my information correct? If the lockout isn't necessary why is it there and why would it be okay to defeat it?

Ultimately the lockout is there to protect the overdrive. It will likely be terminally damaged if you select reverse gear with the overdrive engaged and then let out the clutch. Parts of the OD are designed to rotate in one direction only.

I can appreciate one attraction of OD on 3rd, for overtaking on A roads. Rather than sitting in 4th and changing down, you would sit in OD 3rd (just bearable at 60-ish) and flick down for overtaking, which is quicker and smoother than a manual change could ever be. I wouldn't fit this because I don't do a lot of cross-country driving, but I dare say there are some who do. Tom

OH that would be bad