automatic transmision, shifting while car in motion ?

****While not recommended, an accidental shift into Reverse like this normally does not cause a problem. ****You are putting an abrupt load change on the axles, CV joints, etc when you bounce from Reverse to Drive without coming to a complete halt. It is like anything else you abuse mechanically...you may get away with it for a long time, but you are likely to experience failure moreso than a person who drives gently.

If you didn't feel anything there is probably no consequence to it. He may have moved the lever so fast that it never even tried to go to reverse. And if it did, apparently you were rolling fast enough that the transmission locked it out of reverse. Next time you use your friend's car, feather the clutch a bit.

Since you have an electronically controlled transmission, probably not. That said, doing stuff like that is not very kind to the transmission and drivetrain.

If you have a problem, it will show up 60,000 or 70,000 miles from now due to premature wear.

Absoultely!

Shifting from reverse to drive and vice versa while the vehicle is rolling puts premature wear on the friction surfaces in the transmission. Instead of lasting 200,000 + miles, it may only last 100,000 miles.

Unless you are 17 years old driving the family Motorhome on a cross country trip and it locks up the transmission. Thereby spending a wonderfull two days in some small town in the middle of no where. Dad was a good guy, only told me not to do that again :)

10 mph is pretty fast- you'd have FELT it (but good!) if the trans had actually engaged. My guess is that the electronics didn't allow it.

That depends on the transmission design, so *in general* I'd have to say its a good practice. That said, I rarely do. I just shift while gently rolling, because none of my transmissions are bothered by doing so (some transmissions utilize an overrunning clutch in low gear that would be damaged by being forced the "wrong way." )

Um, what're ya sayin' Ray? payback is a bitch?

I'm not the one who posted that, but I like the idea! Another possibility is to demonstrate how to shift a manual transmission without the clutch.

It can be done, if you match the revs....... but why do that? The more RPMS when you attempt a clutchless shift, the better, right?

-LMB

I think payback should be roughly equal. You can shift a manual transmission without using the clutch but many people do not know that so you can scare the taillights out of them without actually doing any harm, just like they did when they shifted your transmission to reverse. Feathering the clutch would actually do more damage than a clutchless shift.

I know, but if you don't match the RPMs properly, then you grind the living shit out of the dogs teeth, and THAT would make a lot more noise... (but not TOO much damage)

-LMB

I realized that right when I clicked Send. Yeah, there have been times on

3 Yotas where the Master has given out and I've had to hit the syncros myself!

Thanks to all responses and i was a little relieved

*BUT*

I may have spoken to soon, it seems that the shifting is more clunky than prior to shift incidence.

by clunky i mean when shifting from Park to Rev at rest, it seems that there is more clunking surging as tranny engages, and the same for Rev to Drive, the tach shows idle below 1000 (est 750 -800) so i don't think it is a high idle issue.

Plus there is some odd shifting behavior at low speed start / stop

at Starting there seems to be a bit of LAG before picks up when Stopping the car (sometimes) surges/lunges a bit just before car comes to a stop

Lunge mostly occurs under condition of driving along 45 mph then stop/decelerate rather quickly and then at about 5 mph a small hiccup/lunge.

Anyway if you have any advice on this

Help appreciated.

Thanks again to all that responded robb

Sounds like something is slipping. I would get the transmission fluid changed, keeping an eye out for metal particles or friction material in the drained fluid.