Notchy shifting transmission, GL-5 rated fluid doing this ?

[ShadeTreeDSM]

i just rebuilt my transmission and has all new syncro's. 93' awd trans. i put new shifter cables in, new clutch fork & fulcrum ball, new clutch flywheel & throwout bearing, & a Symborski shifter kit. only thing i havent done was put the roller bearing upgraded on the end of the shifter cables were the rubber ones need to be pressed out.

i work at chevrolet and i rebuilt the trans there and the only fluid i had around me was some GM Limited Slip GL-5 75w-90 gear oil, i feels like the trans was better before i built it. its really notchy feeling and grinds when i downshift into 2nd gear, also my reverse also grinds sometimes. could this fluid be causing this ?

what trans fluid should i be running ?

 

[bmoha2]

Full synthetic! My tranny also did not like the GL-5! There are quite a few other options out there as well. redline really seemed make my car shift like butter.

 

[twicks69]

Get that fluid out of there.

Hell, standard 80/90 will be better. Redline MTL or MT-90 would be good for you.

Also, did you inspect/replace the shift forks, or hub/slider assemblies?

 

[DGajre777]

I run 2 quarts of Redline Light weight shockproof gear oil with 0.3 quarts of Redline heavy weight shockproof gear oil, and heavy in the transfer case and rear diff.

I ran Pennzoil Synchromesh for a year and it came out looking like water.

 

[Avionixx]

I ran Pennzoil Synchromesh for 500 miles in my old trans and it came out looking like water too. I don't think I've ever seen an automotive lubricant drain out so fast and the worst part was that it didn't even help with the shifting.

For my TRE trans I run Redline MTL.

 

[ShadeTreeDSM]

Get that fluid out of there.

Hell, standard 80/90 will be better. Redline MTL or MT-90 would be good for you.

Also, did you inspect/replace the shift forks, or hub/slider assemblies?

i replaced all the shift forks. the hub/slider assemblies i did not, except for the 5th gear one.i thought ordered 1st/2nd assembly but when i got it it said it was for the 5th gear. so i hope my hub/slider assemblies arent whats screwing me over

yea when i poured the pennzoil syncromesh in it was like water. it didnt help my shifting at all.





Im going to pick up some Redline MT-90, put the 2.3 qts of that in, thats what shep recommended.

 

[twicks69]

I hope that it isn't your hub/slider assembies also. What I usually do when doing my transmission, or a customer's transmission rebuild is take high resolution photos of EVERY part reused and new prior to installation, and after installation so that if there are any questions after it is back together, I can easily see through the photos what might be causing an issue. It is definitely a good thing to do when you want to cover your butt on a transmission rebuild if it has difficulties or breaks prematurely.

Also, if you are High HP (500+), then I would go with Redline Lightweight Shockproof instead of the MTL or MT-90. Also, I should mention that I have had negative experiences with both the MTL and the MT-90 in my car. If it is a standard street car, they should be fine, but I would reccomend the MTL OVER the MT-90. The MT-90 had breakdown issues in a few transmissions of mine.

i replaced all the shift forks. the hub/slider assemblies i did not, except for the 5th gear one.i thought ordered 1st/2nd assembly but when i got it it said it was for the 5th gear. so i hope my hub/slider assemblies arent whats screwing me over





yea when i poured the pennzoil syncromesh in it was like water. it didnt help my shifting at all.





Im going to pick up some Redline MT-90, put the 2.3 qts of that in, thats what shep recommended.

 

[ShadeTreeDSM]

Also, if you are High HP (500+), then I would go with Redline Lightweight Shockproof instead of the MTL or MT-90. Also, I should mention that I have had negative experiences with both the MTL and the MT-90 in my car. If it is a standard street car, they should be fine, but I would reccomend the MTL OVER the MT-90. The MT-90 had breakdown issues in a few transmissions of mine.

for now i plan on making 400-450 wheel horsepower. daily driven, shouldnt have much issues for now, down the road ill get a fully built trans and use the good stuff.

 

[JackM]

If the sliders had witness marks on the teeth, they should have been replaced. Grinding is bad and means either the synchro rings are wiped out or the sliders are worn down. I would also check to see if your clutch is dragging.

Jack