I was running some errands with my '73 1800ES, and after driving most of the day on the highway and around town, my BW35 doesn't shift into 3rd. It'll go through first and second, but then I don't feel the usual shift into 3rd at around 37mph.

I first noticed it on the highway, it had been running fine, but I had to accelerate uphill onto the highway pretty quickly, so I'm wondering if this could be the cause. Maybe the kickdown cable? The car has 77K on it, and both the oil and transmission fluid seem normal. Could something be out of adjustment, or is this another reason to do an AW70 swap?

It seems like the shift linkage needs to be adjusted. It shifts into 3rd fine if I nudge the shifter a little towards "N" so it looks like it was just in "2" even though the notch in the shift plate would make it seem like it was in "D"

It's been a very long time, but I seem to recall having worn out bushings on the shift linkage of my '72 140 series cars.
Perhaps that is something you should consider inspecting too.

Yes, check the rubber bushings. I had to replace some of the bushings and adjust the linkage on my 90 240’s AW70.
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Will I buy another Volvo??? We'll see....

+1 on the linkage bushings. They are a sort of nylon. Buy a complete set. Not uncommon to find that one or more has disappeared completely. Job much easier if the car is up on a lift. Don't make any adjustments to the rod lengths until after you've fitted the new bushes and done a road test. No adjustment should be needed if all was working fine before you started to get this problem.

There are 2 linkage arms and the bushings are different on each end of each arm.

Both bushings are NLA from Volvo, but I have reproductions to replace both bushings.


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Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90502
hiperformanceautoservice.com or oldvolvosonly.com

maybe the motor mounts broke??