Automatic Gearbox Problem

[Luins]

Being something of a non-technical owner/driver, I wonder whether anyone can tell me the cause of the problem from the following symptoms: sometimes it will roll when in Park (judders a bit); it will sometimes not start (it thinks it's in gear.  Moving the lever about a bit will convince it it isn't); the lever will not stay in 2/1 but the gear is engaged.  Not serious but slightly annoying.  Thanks in advance folks.

[Travis71280]

I don't exactly know why they do this, but any automatic transmission will move a little in park whether its MB to a Chevy TH400. I think this has something to do with a fail safe mechanism within the transmission to protect it from damage if you accidently throw it in park while moving . Don't know about the juddering though. As for the lever, it may just need to be adjusted from the cable becoming stretched out from age. My truck does the same thing.

[Luins]

Thanks Travis.  I'll investigate further.  As I said, not serious, just slightly annoying.  Cheers

[xcashewx]

i had all the same problems as you.
try your transmission mount.

when mine was bad i'd put it in park and it would just roll down a little then come to a stop.it would not roll down at all unless i pulled down on the lever .
transmission mount can also be why the lever wont stay in 2. mine would be in 2 but always seem to end up at 3 even though it clearly was in 2nd. now 2 and 3 are very distinct positions.

as for the starting issue. check the cable on the neutral safety switch. since it obviously works, its just off adjustment, easy fix.

[geezer]

Had the same problem.  The solution was to replace the bushings on the shift rod and the bushings in the shifter housing.  Works fine now.  Items 45 & 48 in the link.

http://www.sls-hh-shop.de/index.php/cat/c64_27-b-Automatic--Linkage-and-Connecting-Parts.html

[ja17]

Hello,

Yes shifter bushings could be the issue. A bad rear trans mount can cause these issues.  Lastly the length of the shift linkage rod is adjustable.  It is often bent during removal of the engine or trans and may need a length adjustment if everything else is ok. The nuetral safety switch is mounted on the firewall and is moved by a cable which is also adjustable.

[Luins]

Thanks everybody!  Your suggestions all much appreciated and noted!