Hello,

I am pretty new here and have a couple of questions. I have a 85 gs with a gsl rear-end and a manual transmissoion. I am going to change the transmission fluid and need to know if you can just use the GM Syncromesh and fill it up with just that. Also, do I need an additive to the rear end for the LSD? Any help is greatly appreciated.

Thanks,
Chris

 

im pretty sure you can just use any manual tranny fluid. and also, there are gear oils made only for LSD rears vs. open diff rears. for racing i put the non-LSD oil in the LSD so it grips even better but im pretty sure you dont wanna do that for street driving because it tends to chatter or grip too hard.

--eric

 

Also, my second gear syncro is going out, that is why the GM Syncromesh. I have heard it works wonders.
Thanks,
Chris

 

Not sure if it helps, I used mobil synthetic gear oil in my tranny and it "felt" better to me. Basiclly if your syncroniser is going out it's going to go out. The best thing to do until you get a rebuild or another trans. take a pause shifting between 1st and 2nd and when down shifting heel/toe and you may also want to double clutch. If you do that you'll be doing most of the work for the syncro, and it will last longer.

 

Gm Syncromesh is Magic Juice for you transmission!

I had a terrible time shifting into third under a load in my GSL-SE untill I put some GM Syncromesh in on the advice of a 3rd gen buddy. It shifts smoothly and seemlessly now. Decent price and plus it's supper easy to get! For the rear end I used some Castrol Diff fluid that has the LSD stuff already mixed im, can find it at almost any parts store.

Use a manual trans specific fluid, the regular gear oil at the parts store will actually eat away at your bronze synchronizers and make things worse.

 

Thanks for the help. I have one more question. In the book, it says to use some sort of pump when adding the fluid. Is there another way to add it, like sticking the bottle in there and squeeze it or what?

Thanks,
Chris

 

The filler plug is on the side of the tranny and is hard to reach without a pump or something. I put it in through where the gear shift goes but that is alot of work. Maybe a long hose or something to reach there.

 

I called up GM and they said their "special GM syncromesh fluid for manual trannies" is no-longer produced... why do I get a feeling I wasn't talking to the right person...

 

That's what I did, just had to keep refilling the bottle as you'll only be able to get about half in before you run outa squeeze, so top it up and continue fulling

 

buy a suction gun..... WELL worth it and probably cheap (theres not much to them)

makes adding rear fluid and tranny fluid ALOT easier.

--eric

 

Definitely. It saves a lot of time spent cleaning the smelly gear lube off the floor.

 

I've heard that using ford type F in a manual transmission works wonders, even if the trans was "designed" for gear oil. The theory is sound - the conditions in a manual trans are much gentler than in an automatic, and the thinner ATF works just fine. I'll try it out and see how well it works on my balky 2nd gear synchro.

 

Ok, I re-read the bottle, it is Penzoil Syncromesh. It is for the GM cars, but is made by Penzoil. Does it take a little driving to help the syncro or will it just work instantly?

Chris

 

keep us posted

 

I have a bad 3rd syncro, tried redline, made no difference. I'd like to try the pennzoil stuff, though.

 

I need to do something, I grind a little when going to 5th. If i go real slow its ok, but pop it in there, its GRRRR

Wonder if I need to change fluid in that 88 t2 tranny? Man that sounds like a FD, with the grinding in 5th problem. The trans was out of a 88 t2 66k on the odo, wrecked in the side.

 

I prefer a nice clear tube (home depot - 1/2" i.d.) stuck onto a funnel. Drop the tube down through the engine bay and stick it into the fill hole. With this method you can have the car un-jacked for a level filling plane so there is less chance of over/under filling. Same goes for the rear end, except hold the funnel near the rear bumper or the passenger side rear wheel well.


For those that have grinding problems, remember to check your shifter bushings as well as your oil before replacing your synchros.