Todd-67

I have a 1967 Inline 6 Automatic. I've started to do some restoration. I didn't run into this problem until I drained the transmission fluid. After the drain was finished, the car would roll forward, but I can't get it to roll backward. I've jacked the back end of the car up, to back it up when needed. When I have it in the air, if I rotate one of the rear wheels backward, the other rear wheel will rotate in the opposite direction.

I'm not an expert, and this is my first resto. Any ideas or help would be appreciated.

Thanks

Todd

dcohen

the reason the wheels turn in the opposite direction is because of the differential

as for the rolling forward and not backward, have you tried filling the tranny back up with fluid and running the car?

if it is just a matter of needing to move the car around then you could always just pull the driveshaft out for the time being

kalli

this is perfectly normal for open rear end. not to worry
check out this page (nice graphics):
http://auto.howstuffworks.com/differential2.htm
if you look at those graphics and imagine turning one wheel while holding the pinion static, then you'll understand why the otehr wheel turned the opposite way. has nothing to do with your forward/backward problem

JHPSTANG

That graphic is amazing. I just learned!!!!

Todd-67

[QUOTE=as for the rolling forward and not backward, have you tried filling the tranny back up with fluid and running the car?

if it is just a matter of needing to move the car around then you could always just pull the driveshaft out for the time being [/QUOTE]

I haven't filled the tranny back up with fluid yet because I'm in the process of breaking everything down. I've removed almost everything from the engine compartment, as well as the gas tank. So... starting it up is not really an option at the moment.

I may do as you suggested, and pull the driveshaft, until I get back to the point replenishing fluids and getting the engine running again.

Thanks for the suggestion.

Todd-67

Thanks for the link to the graphics. It is a good visual, and makes sense regarding turning the wheels. But should this still be engaged if the car is in neutral?

109jb

Neutral refers to the transmission, not the car. The transmission does all the gear changing and is ony hooked to the rear end via the driveshaft. So yes, the differential works all the time, even when the transmission is in neatral.

Todd-67

Thanks, I'll be more specific next time. So.... "The car" rolls forward but not backward when I have the "transmission" in neutral. Would this be a transmission problem or a differential problem?

109jb

I wasn't trying to be a jerk, but I just re-read my previous post and even I thought I was. What I was trying to do is just explain that since the differential is only connected to the transmission by the driveshaft that shifting can't have any effect on the differential. Sorry if it came across wrong.

As for your problem, I would suspect transmission. The differential portion of the rear end would not have anything to do with it. I suppose it could be something to do with the pinion, but I doubt it. It could also be the brakes dragging more in one direction than the other. I had a car that the e-brake wouldn't hold the car from going backward, but going forward it wouldn't budge. Again though, I doubt that is it. I would unhook the driveshaft from the rear end and tie it up out of the way and see if the car rolls OK. If it does then it is transmission.

Todd-67

No problem.

Thanks! That answers my question as to where I need to start in figuring out what the problem is. It sounds like the transmission is the likely culprit. I'll disconnect the driveshaft and go from there.

Thanks again, I appreciate the response.