I've looked at these 2 pics and cannot see a difference in them. 1st pic is the 401882 for the 1968. Pic 2 is the 3986863 used from 1969 thru much later years. I'm not always the most observant. Am I missing something?

 

Lot of time, parts made to fit different years has a number change. If you use the old number, and they look up the part number, may say number was superseded, to the new number.

 

Thanks, I should have noted that I checked GM Parts Wiki on both these numbers and there is no supersession showing on either. It's also notable that none of the aftermarket suppliers list a kickdown switch for a 1968.

 

Can't tell for sure without seeing them side-by-side, but it appears that the round peg that is pushed by the accelerator pedal arm is longer on the second one. That may be a redesign to allow that same part number to be used on multiple applications.

 

Especially with electrical parts, the difference could be completely internal, invisible, but still make a drastic functional difference. For example, the switch inside one might be normally open, the other normally closed. (Though I doubt that's the case here.)

 

Good point, I guess we'll find out. Since the 1st one is for sale for $150 and I can get a new one of the 2nd type for less than a third of that, I'm gonna take a chance I can make the 2nd one work. I'll post results after I try installing...

 

The TH400 (and Jetaway) kickdown requires a N.O. switch that closes at W.O.T., so that's not it. On the other hand, it COULD be a change to the internal contact material, lubricant, or something like that.

I wonder if this has anything to do with the fact that the Junkaway trans was only offered in the 1968 and early 1969 model years before being replaced by the TH350?

 

Not sure... Oldsmobile parts catalog list fitment on the 1st one (401882) as 1968 F-85 and 1968-1970 Toronado only