tomsawyer

Hi Everyone - I'm a new owner of a 2003 with 94k. I am the 2nd owner and the original owner completely dealer service the truck. Even so, there are a couple of issues but now a really big one has crept up.

I have driven about 1500 miles over the course of the last 3 months w/o any transmission issues but now something's up. Right now, I have no reverse gear and the trans is not shifting past 3rd gear. I took the truck to autozone and got the codes read. Only one is present - p0756. If I disconnect the battery and reattach, the gears come back but after a short while, the condition returns. I believe the trans A750F.

Do you think this is a tranny issue or something outside of the trans failing which tells the trans not to shift past 3rd gear and no reverse?

Thanks to all who answer.

hankinid

It sounds more related to the electronic trans controls v. the tranny itself. I'm basing that on the trans going back to normal for a bit if you disconnect the battery and reconnect.

Steve

isfdude

iTrader: (11)

Something is slipping inside. When you reset it the computer doesn't have the error code so it will remain normal until it replicates the problem again. Something either might be slipping due to a Stuck solenoid or bad fluid and clogged filter.

tomsawyer

The code I got does refer to a solenoid. However, I was thinking/hoping that maybe something outside the trans was causing the issue and perhaps the same thing happened to someone else on the board.

If I remember correct, trans oil was changed at 89k by the last owner, at the dealer. Not sure if it was a complete or partial flush. When I looked at the dipstick, the oil was very fresh, no odor and no residue.

isfdude

iTrader: (11)

Ok a flush is no good as it will push all the crap to the filter. If I do flush mine I then drop the pan and change the filter too and seal it up and pump new dealer fluid in to it. Is there paperwork showing it was done at the dealer? As most people will say anything just to sell a car these days. Usually if a solenoid is failing the best way to fix that is replaced that solenoid.

tomsawyer

Thanks isfdude. The evidence of the oil change is based on the VIN # info when I registered on the Lexus website, plus the info that came from the carfax. I don't have the printout in front of me but the previous owner, at about 89k, essentially did the 90k service (timing belt, water pump, etc) and one of the other items they did was tranny service. And, based on what I'm seeing, the tranny fluid does look fresh.

Nonetheless, I was hoping that perhaps someone else had the identical issue of no reverse and no 4th/5th gears and I could at least, for the mean time, maybe throw a part at it to hopefully rectify.

I've been doing some research online, the little that's there, and come to find out that many times this condition may not be necessarily be actually caused by the solenoid itself or internal tranny components but rather the Park/Neutral sensor module, low tranny fluid, the ECM (I really hope its not that!) and/or a speed sensor. But unfortunately, I can't find anyone that has run across this particular issue and posted the fix for it.

isfdude

iTrader: (11)

are there any codes? There should be more than one coming up. You need to run a good scanner that can read the transmission codes so you can see what is going on. A base scanner will not be good.

tomsawyer

Figured I'd update everyone - I took the truck to 2 different tranny shops. One shop is a "friend" and all he does is trannys. The other shop is an AAMCO shop that's been around and owned by the same guy for 35 years. Both said the internal seals were shot. Again, I'm not very techy or mechanically inclined so I'm not sure what seals they're talking about. Anyway, my "friend" was going to rebuild the trans and AAMCO install a remanufactured one. I have another guy who's a toyota master mechanic and he recommended the reman which comes with a 3 year/50k nationwide warranty so I figured that's the way to go.

Truck should be ready the end of the week. I'll let you know how it goes.

hankinid

Is the Toyota master mechanic recommending a factory-rebuilt tranny through Toyota, or a rebuild through AAMCO?

I'd recommend the former and that seems to be the best way to go if you plan on keeping the truck.

Not sure what I'd think about the AAMCO rebuild.

An update would be appreciated once she's out of the shop.

Steve

tomsawyer

Its a long story but the Toyota mechanic was supposed to work on the truck but never got back to me. Anyway, I went with AAMCO and picked up the truck yesterday. The trans is a reman unit, not rebuilt. Picked her up last night - now I have 5 working gears plus a working reverse. So far, so good. I'll keep you posted after a couple of weeks driving.

isfdude

iTrader: (11)

That's good to hear, make sure at 30k you get the pan dropped and install a new filter and dealer fluid to keep it that way.