Strange transmission anomaly shifting into Reverse

[beeftube]

Last weekend something weird happened that I'd never experienced before (across 2 4Runners, both V8's, both 2006's).

I cranked the truck up from a cold start in the garage, 2-3 seconds later shifted from Park to Reverse to back out.

Nothing happened. The indicator light said it was in Reverse, but I never felt the typical gear lockup. It just stayed put like it was still in Park. I VERY gently eased off the brake just in case it locked up without me realizing it, but nope, it just stayed put.

I decided to give it just a little bit of gas to see if the motor would just spin freely like it would in Park or Neutral, and as soon as I did that I heard two loud "pops" and Reverse engaged and I started moving backwards.

This if the first time I've ever had that happen, and it hasn't done it since. The truck only has 61,000 miles on it (very easy, well-maintained miles at that), and otherwise the transmissions always shifts normally with no slipping.

Anybody else had a similar problem? Normally I'd think a fluid flush would be in order maybe, but of course this transmission is sealed...

 

[BlackWorksInc]

Was it really cold outside? That is a strange issue...

I would try a fluid flush, just because its a "sealed" transmission doesn't mean you don't change the fluid on it. There a ton of posts regarding how to do this.

 

[TRDCal]

I don't have any insight but I will tell you that I've had a similar problem: http://www.toyota-4runner.org/4th-gen-t4rs/107446-stuck-no-reverse.html. I've seen it before on the forum with other members but the problem never seems to reoccur so I haven't worried about it too much

 

[WXman]

Was the e-brake set? Sometimes if it's cold the e-brake will "freeze" and when you put the vehicle in gear it won't move. Applying throttle will break the e-brake free with a couple of "pop" sounds and then you're moving again. Just a thought...

 

[Stuck CAPS]

This happened to me when I blew my rear-end, and a little bit before, so if it continues to happen, get that checked out.

 

[beeftube]

So -- no, it wasn't cold out. Maybe 58-62 degrees F. Not like the other "stuck in reverse" thread as I wasnt in 4Lo or messing with the transfer case at the time.

e-Brake was not set -- that's the first thing I thought of, but I didnt feel the usual sensation of when the transmission locks into gear. With my foot completely off the brake on level ground, it wasn't moving.

I'll look into a fluid flush.

 

[NJshadow93]

No bumps, or rocks, or anything else behind the tires right? One time I ran my truck through a touch free car wash to get the salt off, it was bout 15 degrees outside at night. I got back in my truck an hour later and had a similar sensation, but I didn't have to hit the gas to get it to go. I put it in reverse, took my foot off the brake and POP and then I moved. It was just ice caught up in the wheels from the car wash (I had ice all over the truck because of it). That's why I ask if there was anything your tires may have been caught up on.