shifting issues

[Tjay]

Ok the car is a 88 7mgte with r154.
the car has sat in the garage for a year since I bought it. i've been working on it and getting it back into running shape. so I took it out for a test drive today and it is really hard to downshift, like you have to slam it to get it into gear, this only seems to be a issue when downshifting when the car is moving, if I wait till the car pretty much stops, it shifts OK. upshifting is fine, a little notchy, but ok.

car had a hacked short shifter put on before i bought it. I am wondering what this could be. a shitty job of cutting the stock shifter? maybe I just need to drain the tranny fluid and replace with MT90? could it be synchros? clutch slave cylinder? or as simple as the shifter bushing or socket?

I will be troubleshooting tomorrow, but I was just looking for some feedback from the experts at SM!

thanks alot guys.

 

[gaboonviper85]

In all gears or mostly first and second? The trans is built to not be able to be down shifted at higher speeds in those gears...stop slamming!

 

[Hmong_1G]

^^--- YEP. Check your shifter bushing. There is a video on youtube that a member here have on bad bushing and replacement. Just did mine. Can't wait to see the outcome ( my old one literally incinerated)

 

[Tjay]

it's definetly not normal, it occurs when downshifting from any speed..i basically have to wait for the car to come to a complete stop to be able to get it into gear. and this problem does not happen on either of my other 2 supra's. I haven't gone past 3rd gear though because ive just been test driving it around the parking lot, because it is not registered or insured yet.

im going to pull the shifter today and check out the bushing and socket, I think i have a few bottles of mt90 kickin around so I might aswell do that to. just wondering what else could be causing this?

thanks

 

[Tjay]

checked the socket and bushing, they both seem ok..I was suprised the bushing wasn't disintegraded. it must have been replaced before I got the car.

anyways, I took it for another test drive today and noticed the clutch pedal is a little bit sticky. I'm guessing (hoping) I just need to bleed the system, but I will check the master and slave cylinders for any leaks tommorow.

Could air in the system or a faulty master or slave cylinder cause hard shifts?

 

[RedGT]

Yes, the clutch may not be fully disengaging when you push the clutch in. Usually you can check it by revving the engine with the clutch depressed and trans in first gear. If it creeps then its not fully disengaging the clutch.

 

[Tjay]

well I`m starting to think it might be the hacked short shifter..I topped up the clutch fluid and bled the system, checked for leaks, clutch engagement is much more smooth and consistent now. but it`s still hard to shift. I`m wondering if the shifter is the same for the W58 and the R154, if so I will try and swap shifters and see if that makes a difference.

 

[ben1984j]

You didn't say you had put in the MT-90, if you haven't done that yet it's definitely a good idea. If you have the wrong kind of gear oil in there (like anything that has friction modifiers), that could be keeping the synchros from working properly; if not the MT-90 will be still be an improvement over whatever is in there now. Your problem does sound synchro-related; if ease of shifting depends on speed then I doubt it has to do with the short shifter...

 

[adampecush]

Can you at least rev match into gear?

 

[Tjay]

yeah I was thinking about it some more, if it shifts thru the gears fine (a little notchy, but ok) when its not moving, but has a hard time downshifting when rolling, I fear it could be the synchro's, its most difficult downshifting into 2nd. I have the day off today and am going to spend some time working on the car, MT90 will be added in place of whatever is in there now. hopefully that helps.

and double clutching does not help the situation.

 

[Tjay]

drained the old stuff and put the MT90 in..made a huge difference, it's still harder than normal to downshift to 2nd but it'd manageable now. before it would refuse to go into gear till the car was basically stopped. I only took it for a 5 minute drive and could definitely notice a difference, hopefully it will get better the more I drive it. first time I have used MT90, and I am sold on the stuff.