[428 tempest]

66 gto with new wiper transmission and new wiper arms. Arms only go on halfway even with a little encouragement from rubber hammer. put on my 65 and they fit all the way down. tried my wipers on 66 no go. used caliper and both seem same ? any ideas?

[428ho4spd]

Sounds like an issue with the splines on the new transmission not mating with the arms.

[428 tempest]

But they both go half way on , i could see if they wouldn't even start? Splines look good also.

[242177P]

Originally Posted by 428 tempest

But they both go half way on , i could see if they wouldn't even start? Splines look good also.

Caliper is good, but I expect you'll need many more measurements. I expect they use an interference fit (slight taper). If the splines were straight, the arms would slip right on and off, never getting tight. If the splines are deep enough, you could get away with just sanding down the outside diameter a little at a time? If the splines themselves aren't large enough (or deep enough?) work them with a file? A permanent marker might help show where the binding is at it's worst? Dunno. Thinking out loud.

[400 4spd.]

It's a manufacturing flaw with the transmission, and the vendors know it. I called The Parts Place to order one for a '67, and the sales guy told me I would probably end up returning it, so save the package! He said there was one company manufacturing them, and most had the same problem that you see.
He was right. I eventually bought an original from another member here and restored it.

[428 tempest]

Bought used transmission threw the new one away that came from the Parts Place . Why do they sell junk they know won't work???

[GT182]

Yep, best to find a used one. I'm 99% positive someone on here has one. New is crap. Go to the 61-77 Parts Wanted section to ask for one......
https://forums.maxperformanceinc.com...play.php?f=448

[HoovDaddy]

Same problem with a '66 Chevelle 2 years ago. Ended up rebuilding the original transmissions and the repop arms fit right on. Junk repop trans.