I am picking up a 85 today. The previous owner has described that the auto shifter will not engage park. He has been starting and stopping in the N position. Occasionally, at speed the transmission will randomly downshift.

I have not owned a auto since my first 928, 10 years ago (3sp). I have been studying the WSM and am hoping that it will be remedied by adjusting the selector cable.
Based on the symptoms, does this sound like a cable adjustment or a modulator pressure issue?

My question is: After detaching cable from operating lever, is it clear when the operating lever is in the neutral position? Further, is adjusting the cable pretty straight forward, read "easy".

Thanks for any BTDT advice.

 

Yes its easy.
Trick is getting the levers released that hold the accordian cover in place on the console.

I'd probably get it into the air, disconnect at the transmission, and try by hand (with vice grips) to select park. One here had the parking pawl broken inside.

Then, I'd probably check out the movement of the shifter and cable itself.

If the boot is broken by the transmission it can get sand into the cable that will wedge it from moving.

Regarding random downshifts, not certain how many ways that can occur. Shorted kickdown switch (or remnants of a bypass switch) or overly tight bowden cable might have that effect. Not sure what else. Start with inspection of system + fluid/filter change?

 

A few pictures

 

Thanks Chris. Third picture is very helpful. It may be Monday before I have it up on stands.

 

Also, forgot to mention that I have a trans kit from 928 International and 6 quarts of Redline ready to go

 

I would use Dexron VI...

 

Wally, is that because it is an auto or just on general principle?

My 5 speed loves the redline fluid.

 

Am using Valvoline high mileage Dexron, in the red bottle, in the trans.

Rear end gets gear oil.

 

Thanks Chris made it home safely and it's parked until next week. I hope to know more once I've got under it and fiddled a little.

 

The auto specs say to use Dexron. Dexron VI is the latest spec from GM - all previous specs and licenses have been canceled, so there is no longer any other GM-approved Dexron available.

All available info indicates that Dexron VI is better than any previous iteration of the fluid, and that the specs are much tighter than ever before.

I don't have an auto 928, but installing the VI in our high-mileage Suburban resulted in noticeably better shifting.

 

Thanks Wally. I appreciate your thoughts and your info.
I was @ I75 & 575 when I read you first post.

 

Well I got her jacked up and just tried to investigate the park issue. The three pictures are 1: neutral, 2:reverse, and 3:Park. The cable has wear and it looks like there is an aluminum shaft/guide/cable housing that may have broken. I am sure that somebody can take one look at the pic and tell. Anyway, I was able to manipulate the selector lever to the park position. It stayed there with no problem, the instrument panel indicated that it was in park for the first time. We were unable to duplicate that using the shifter in the cabin.

Can the aluminum sleeve be repaired or replaced??

 

Buy the whole cable assy. Can't remember if the boots come with it or separate, but be sure to get the boots.

Here's one.

 

Thanks Chris. May Paypal acct is kind of skinny right now. I guess I need to go pull some goodies off of the parts car.

Thanks for all of your help.

BTW I did pick up some Dexron today. I hope to smooth out the shifting with a fluid and filter change.

 

still have the black back seats????

PM me....