84REDCROSSFIRE

Reverse lockout solenoid was going bad. Trans would grind and try and go into reverse on a 4-5 shift atleast once a day. Found a few posts about replacing it, at almost $150 for the part alone. So I figured if I could get to it easy, I would mess with the solenoid first to see if I could "Fix It". With the car backed on to ramps the solenoid was very easy to get to with a 1/4" drive 13mm deep socket, If you can change your own spark plugs you can probably remove your own lockout solenoid. Its on the top of the trans, pass side. The wires unplug from the back of the solenoid, typical 2 wire GM weathertight plug. Lift tang slide plug out.

With the part removed I seperated the solenoid from the aluminum housing, next with snap-ring pliers I took it apart to remove the interal piston and spring. With it apart I used a little peice of scotch-brite pad, and cleaned up the bore of the aluminum housing, and cleaned with the same pad the outside of the piston. Sprayed both the piston and the housing with Brake cleaner. Greased both the bore, piston, and spring with Hi-Temp wheel bearing grease (not too much, just a coating) and slid it all back together, with the snap ring holding it all together again. I worked the piston back and forth a few times to make sure it didnt bind.

With some 3 in 1 oil I lubed the solenoid nipple, allow some oil to creep past the nipple by pushing it up and down with a flat screwdriver. Then I worked it up and down with some little jumper wires and 12V from a battery, wire polarity doesn't matter. If the 12V don't work, then the solenoid is bad. Screwed the solenoid back together into the piston housing, little bit of ATF fluid on both O-rings. Installed the whole thing back into the trans, (only one 13mm bolt holds it in) and plugged the wires back in. It's been a week of driving now and no more 5th gear reverse grinds. Cost $0.........COOL

Link to Thread with some picks of solenoid, and good repair right up
http://www.ls1tech.com/forums/manual...-solenoid.html

Atok

Mine did this for the first time last week. I'll keep this in mind if it does it again. Thanks for the post.

CHJ In Virginia

Good write up on fixing a common problem - thanks for posting.

Paul Wood

Great post. Even though I have an A4 ZI appreciate the information and the way that you wrote this up. I am sure others will find this very helpful and encouraging. After all, that is one of the best things about this forum!

rebelheart

Nice clear discription of a simple fix,good job!

LC

Got the same problem with my '99 Coupe.. going to give this fix a try.

cdkcorvette7

Great post, thanks! I'll save this for later.

GM Fan

Ohhhh, thank you very much for this post and the link to the pictures. I take it from the pictures that the Fbody tranny has this more on the top side of the tranny where ours is right up on the actual top of the tranny correct?

I have similar problems with mine wanting to let me hit reverse while moving if I'm not careful, but it's really intermittent. Anyway, I was trying to tell how it would come off by feel one time while bear hugging the tranny and gave up. Looks like it should actually be pretty easy to remove now that I realize it is a single bolt. I was thinking the whole solenoid unscrewed (well I guess technically it does to take it apart once you get the whole thing off the car...) and that was going to be a bitch to do with it on top of the tranny....

I'll have to give this a try some weekend if it gets to bothering me again.

Could very well be that you have/had a wiring/connector problem though. I know with mine when I reseated the connector one time the problem went away complete for a week or two only to come back intermittently...

Hopefully it won't come back and will no longer matter for you, but I think you can avoid hitting reverse almost entirely if you position your hand "properly" on the shifter though; palm towards the passenger and just pushing up and right moving the shifter straight towards 5th. Whereas Grasping the shifter and pushing straight right then up to 5th kind of in two different motions will have you ending up going over to reverse almost every time if the lockout isn't working right...

84REDCROSSFIRE

UPDATE......9/21/11

Reverse lockout solenoid is acting up again after working all summer flawlessly. I was gonna just relube it again, but now GM has a new updated part. Old GM# was 12523300, new GM# is 19178634 and is cheaper than the old one ($87.18 shipped GM PartsHouse). New solenoid looks redesigned, i will post pics of both when I get a chance to swap them out. So maybe GM got the new one right........... can only hope

Bill Curlee

WOW. Outstanding info and well documented Great work!

BC

freeman4ever

Sorry to thread-jack...just adding information for future reference...

Here is the updated solenoid:


Here is the old solenoid removed:


Here is updated solenoid installed:


The updated solenoid barely covers the original opening, due to the 34mm versus 27mm difference in size. Fortunately the internals are sealed up with the large o-ring it employs. Haven't had the chance to test to see whether or not its cured my 5th gear grind yet (still performing other repairs)...but am hopeful.

Bill Curlee

Do you have any photos of the old one apart??


Great pictures!

BC

freeman4ever

Sure don't. May find time to deconstruct this weekend.

X-Ravin

Mine acts up from time to time, inconsistently. Shortly after I got the car it stopped opening to I had to do the left hand muscle into reverse routine. Then after a couple months it started working. Then for a week it was stuck open and I was grinding reverse when going to 5th. Luckily it has been fine the past couple months. I will probably replace it in a few weeks when I do the brakes.

Which is easier to do, unscrew the solenoid or remove the entire housing? I've seen both explained as being the correct procedure.

freeman4ever

Removing the entire housing is MUCH easier. It's only one bolt, and while you will not be able to see it, its easy to feel for it. I think it's a 13mm.

***UPDATE***

After going for a number of drives, I have not had a 5th gear grind yet. However, I did have one incident where I popped out of reverse (while reversing) - which used to happen before with the old solenoid. It only happened once...and it most certainly could have just been user-error.

I was going to open up the old solenoid this past weekend (to post the guts) but was a little apprehensive at doing so until I could confirm the new replacement was good to go. Will tear it apart shortly.

jrgeorge27@gmail.com

I am in this same boat. I had to replace the old one with the new "updated" one, but have issues after getting the new one installed. The one locks me out of reverse 100% of the time, but 1-6 work fine. I put the new solenoid in from GM and now I can't get to 1,3,5,6, but 2,4 and reverse work....any ideas? please help..have a car show in 2 days for charity and car isnt working...

freeman4ever

Could be the solenoid or its connector is not seated properly? Also, not sure that this is advisable, but you could remove the solenoid and go for a short drive to see if 1, 3, and 6 work (I wouldn't chance 5, since it's closest to reverse)? Could be that the new solenoid is wonky...

NatB

The instructions in the manual for replacing the reverse lock out solenoid are quite involved .

Can someone please confirm that you can reach, remove and replace the solenoid on my 2002 Z06 with it simply up on jackstands? I do not want to mess with lowering the transmission or any such complexities.

Thanks

SS2001SS

I did mine on jackstands in the garage without lowering the trans or loosening the cradle. It is difficult/impossible to see all the way up in there but not too hard to replace the solenoid. Doing it this way you have to remove the whole solenoid and housing together (which is easier I think) because you can't really get the big socket up in there to remove just the solenoid. I didn't have that size (34mm) anyway so I separated it on the bench once removed.
Take note of where the wiring goes when disconnecting it. The harness has several connections on it and is routed a certain way and you want it to go back in the same place when re-installing. Again it is difficult to see up there and not much room to work so you have to do it by feel when putting it back together.
I was a little intimidated after reading the shop procedure, but after looking at the diagram and getting under the car to check it out doing it wasn't that bad.

84REDCROSSFIRE

Wow, forgot about this post. The new updated soleniod is the way to go, Haven't had a problem since replacing it. Its not worth the effort to try fixing the old one, just replace with a new solenoid.