Gears grinding, not a drag issue

[Chipper308]

New trans, new clutch, new slave/master. had huge issues getting this trns right, finally its right...hokay awesome...all is good untill the other day my girl goes out to the tore comes back inside and says "it wont go into gear!" shit... okay so it will not go into gear at all, if i start it in gear and get moving down the road it willl shift perfect everytime no questions asked...untill that special stop sign(1/10 stop signs) it grinds again and does not want to go into gear, so i procede to tun the car off put it in gear and repeat.... no issues in shifting under load from what i can tell...i figured the tranny guys f'd me over on fluids so i went and bought mt-90 and put it in my trans/transfer case. same issue. im not losing any hydraulic fluid.... im going to adjust the rod in the a.m...just to clarify to adjust the rod u turn it torwards the firewall until the slave cant be moved by hand anymore, then u back it off a quarter turn at a time untill the slave can be moved by hand again thn u lock the nut down and its good...correct?

Thanks for the responses! also i just ordered my small 16g, installed my aftermarket BOV, uicp, wideband and boost gauges today! once this trans issue is sorted out im rdy to rock! thanks all

oh and i know its not drag because i can put the car in gear and rev the engine and it wont budge, not even an inch, my engagement is also just past half way, closer to the floor but not enough to even make me consider drag. what would make for inconsistent shifting like this? i look into "pump petal" but ive previously backed off the cruise control switch as far as i could, so i cant imagine that is the issue.

Edit: also i doubt this has anything to do with it...but when i press the clutch in, i guess if u find the perfect spot...something squeeks, im thinking its just a belt...but it hadnt ever happened before. i havent been able to replicate that with somone else in the car and look into it myself

 

[1990AWD]

Here's the video on adjusting your master, [ame]http://youtu.be/vYJxQyjIhUw[/ame] and I sure hope you're not actually running MT-90 in the t-case, as that needs to be an actual gear oil.

 

[Chipper308]

thanks but ive seen the video, a few times, i was just making sure that was the right way to do it...and whoops....im very tired haha idk why i put transfer case.

i was allmost going to put something like "dont link me to jacks transmission adjusting clutch video" but figured id chance it.

 

[Chipper308]

Okay tinkering with it today I can ad some things. It drove absolutely amazing all day today accept for when I first started it..had to start it in gear, and once I got home I left it for about an hour n half walked back out and went to put it in reverse....grinding.... started it in reverse and have it like a mini launch in reverse....(nothing took intense) and did the same in first and now it shifts smooth as a babies ass again.... dafuq?! I thought the fluid was off or getting cold but its 65 degrees today with mt90 in the trans changed yesterday, I have the clutch rod adjusted properly, hell I even tried over adjusting it to get more fluid travel thinking its possibly a drag issue and its not disengaging all the way but it didn't seem to make and bit of difference.... once JM on the road and driving it shifts good within reason, no grinding at all....I can even press the clutch rev it to about 3grand and slip it any gear I want, car will never moved forward with the clutch down

 

[97grnrs]

a trans i just put in mine is doing same thing.when its cold it shifts rough as hell, not grinding buti can feel itgoes into 2nd and 3rd rough. once it warms up it shifts like butter.. i tried about every fluid and the best is synchromesh but its still rough when cold

 

[Chipper308]

thank you for everyones amazing help, such a quick responding community ive come to the conclusion the trans has issues when its cold...and i dont mean cold cold i mean just...air tempature...65 degrees out the other day and it grinded untill id been running it for awhile, i ran it real hard for about 100 feet in my drive way, bam everything shifts awesome.... its seems to me like fluid isnt getting to where it needs to be getting too? why would this be? how can i fix it...please work with me here as nobody has said anything at all. and even if this just is the way it is when its cold outside...its allmost undrivable in the condition its in every morning, and i live in MICHIGAN people...it gets cold as balls here and i find it just a tad bit ridiculous that 'oh u ant drive your car bcuz its cold outside" cmon now.... there has got to be something else at work here.

 

[97grnrs]

i talked to the guy from tmz about my same issue , he says poss clogged oil ports on the shafts or even other problems. guess my other trans i going back in soon.. .. or just double clutch until it gets fluid warmed up like im doing

 

[Chipper308]

What is double clutch?

 

[Chipper308]

Nvm, its matching the engine with the trans for a smoother shift. I do this allrdy haha just didn't know the term

 

[JackM]

You say you have a new trans. From who? If it's not from a highly experienced builder then I would guess that your input shaft preloads are way too tight. Your symptoms seem to follow this. The case will expand and twice the rate as the steel input shaft, so the end bearing preloads could be super tight when the case is cold, then once the case expands, it will loosen up.

The synchros job is to speed up or slow down the input shaft and clutch disk when you up or down-shift. If the preloads are super tight on the input shaft, the synchro will have to work terribly hard in order to synchronize the input shaft with the gear you are trying to select. Once it warms up, though, it is loose enough to work better.

Clogged oil holes in the shaft will not do anything to the shift quality of the unit. Many Getrag transmissions are designed without oil holes in the shafts and they shift perfectly. The synchro works by creating friction, so even if there is no oil to be found, it would actually work better. The synchro has to move the oil away in order to work, so I would find it very hard to believe that clogged oil channels is the issue.

I would ask the place which built your trans what they did for input shaft preloads. We spend a lot of time on things like that, but many others just blindly slap them together and issues like this can happen. Input shaft preloads can make or break the shift quality of a trans.

Good luck!

Jack

 

[Chipper308]

You say you have a new trans. From who? If it's not from a highly experienced builder then I would guess that your input shaft preloads are way too tight. Your symptoms seem to follow this. The case will expand and twice the rate as the steel input shaft, so the end bearing preloads could be super tight when the case is cold, then once the case expands, it will loosen up.

The synchros job is to speed up or slow down the input shaft and clutch disk when you up or down-shift. If the preloads are super tight on the input shaft, the synchro will have to work terribly hard in order to synchronize the input shaft with the gear you are trying to select. Once it warms up, though, it is loose enough to work better.

Clogged oil holes in the shaft will not do anything to the shift quality of the unit. Many Getrag transmissions are designed without oil holes in the shafts and they shift perfectly. The synchro works by creating friction, so even if there is no oil to be found, it would actually work better. The synchro has to move the oil away in order to work, so I would find it very hard to believe that clogged oil channels is the issue.

I would ask the place which built your trans what they did for input shaft preloads. We spend a lot of time on things like that, but many others just blindly slap them together and issues like this can happen. Input shaft preloads can make or break the shift quality of a trans.

Good luck!

Jack

thanks jack, i appologize the trans was a TMZ rebuild, so im not very worried about the quality i dont think. please check this new thread for my updates...thanks for the reply! i didnt see you had replied
http://www.dsmtuners.com/forums/drivetrain-tech/463127-st-reverse-grind-new-trans.html