Very detailed!!! Transmission or Clutch Problem

OK I have a 1994 supra tt 6 speed, I bought it about 3 weeks ago from a toyota dealership. The clutch has just been replaced and the flywheel had been re-machined. My problem is that I will be driving in 1st gear and and 2nd gear when I push the clutch in there is a reasonably loud chatter that you can hear from inside and outside the car even if your standing 10 feet away from the car that happens about three times,( clutch in, chatter, chatter, chatter) then it stops.

I also have a problem with when shifting normally into 2nd and 3rd gear it feels like something is hitting it, almost like the clutch isnt down all the way down but theres no grinding just a bump and it goes it to gear. If im driving though and lets say I take it out of first, wait a sec or two, and then put it into 2nd gear the bump is gone.

Another thing that happened a few days ago while I was driving I went to put it into 2nd while rolling at a low speed, the gear started to grind, so I moved the stick up but kept it to the left (in between 1st and 2nd) and pulled it down again, it did the same thing and the gears started to grind so I pulled the stick back to the neutral position (between 3rd and 4th) and then pulled the stick to 2nd and it went right in no problem, the thing that didnt make since to me was that my foot had the clutch down to the ground the entire time from the low speed roll to the transmission going into 2nd gear. If anyone could help that would be great!

i wonder when they machined the fly wheel if they cut it down too much!? i had a 1g AWD talon a few years back and it happen to me machine shop took to much off the fly wheel and the clutch would chatter and would also grind when trying to put it in gear where thats a DSM & we're talking about a supra not sure if that helps :uh:

ok thank you very much, I cant get to a shop that I can trust and that has experience with performance imports for about a week, I just wanted to make sure its nothing to serious because I dont want to mess up my tranny.

I am looking to do the typical bpu upgrades and then if this is the problem, a new flywheel and I know there are a few ups and downs with flywheels, but I would like to get a good, possibly slightly lighter flywheel, but I understand that if its too light there will be chatter, if you have any insight on what would be a good flywheel or should I just go with the trd twin disc set with flywheel, as well as what is the trd clutch set good for hp wise?

If any one has any more insight on the possible problem please let me know thank you!

Best Flywheel
 

Ok so I have a 1994 supra tt, 100,000 miles on it, I might have to get a new flywheel because the toyota dealership re-machined the stock flywheel to much, so what would your suggestions be on an aftermarket flywheel. I am not looking for drag racing or the lightest flywheel made, because I dont want the chatter or problems with idling, just a good one possibly lighter weight like the rsp flywheel, but if you guys could let me know what you would suggest and why. The car is stock right now but I do look to bpu it this summer, il be looking at around 400 450max hp. Thanks

no problem man, sorry i can't give you any insight on fly wheels my car is a auto. search the forums to see what guys are saying about fly wheels MKIV.com has a bunch of info.

Thread moved to the MKIV section.

Who changed your clutch and machined your flywheel? Toyota?
1) It's extremely difficult to machine the oem dual-mass flywheel. Are you sure this was done, properly?
2) Was the clutch plate installed properly? It's possible to put it in backwards (although the clutch usually won't engage if it's in backwards).
3) At the very least, it sounds like the pedal needs to be adjusted to more completely disengage - do you know how to do this?

Note: I just merged this with the other thread - why did you double-post your question?

1) A lighter flywheel is not a "typical bpu upgrade". BPU upgrades consist of a boost gauge, a fuel cut elimination device (eg BCC), a downpipe, and a boost-raising modification (eg. 'clamp mod' or ebc).
2) Chatter is not caused by an aftermarket flywheel, although transmission 'rattle' while idling is. Eliminating the oem dual-mass flywheel passes all minor rpm changes directly to the transmission, which causes the noise. It's not loud at all, but it is noticeable (especially while running your a/c). Chatter is typically caused by an aggressive carbon clutch disc with a non-carbon (i.e. steel) flywheel and pressure plate.
3) You won't need a twin disc flywheel until you upgrade to a single turbo. The clutch you need depends on the max horsepower (i.e. torque) you need it to handle. For BPU, a single disc clutch is more than sufficient. Tell us the max rwhp you will need this clutch to handle, and we can provide a recommendation.

Any light flywheel will make your Supra a bit harder and/or a bit less convenient/comfortable. Can you live with that? For example, when you eliminate the oem dual-mass flywheel, you'll notice a rattling noise from your transmission while idling and your clutch pedal not depressed. Would this be a problem? Also, your Supra will be more likely to stall when moving away from a dead stop (especially uphill)...unless you change the way you drive and increase the rpm. Would this be undesireable?

1)It was toyota and they probably didnt because it was a smaller toyota dealership, so their knowledge was probably limited
2)The clutch engages the but it does seem kind of unnecessarily hard to put each gear into place, not like forcing it in, but like I cant just put it in, I do have to apply a little bit of pressure
3)I dont if its something I could do with basic tool, and not getting under the car then if you could tell me how, other wise I am going to take it to a shop in Tulsa, Oklahoma that have experience with imports and, have been highly recommended from mr2 turbo guys and a few supra guys as well as hondas and other toyota owners, but to start the car, the clutch has to be pressed all the way to the floor, if it is not touching the ground (as far down as it will go) then the car will not start

1) my bad
2) I heard something where you can have your engine set to idle at a little bit higher rpm, like 1000-1200, have you heard of this?
3)max the car will every have is 650wrhp, that wont be for a few years tho, Im just looking to do bpu, and keep the tt set up until I am out of college, so 400rwhp as of know, what do you recommend flywheel wise and clutch wise

Thank you for your help ahead of time

Glad to help! :)
1) No problem at all - just making sure you and others reading this thread weren't confused on the specs for BPU vs. non-BPU/APU upgrades.
2) Of course - but it's only practical to achieve if you're running an aftermarket ECU (eg. AEM). Trying to accomplish this by adjusting the oem throttle body will be frustrating at best. Trying to do this one change by adjusting the oem ecu isn't practical. Note that this will also negatively impact your mpg's.
3) Are you sure you want to buy a 650rwhp clutch right now? Within "a few years" you could easily wear out a less expensive one. For 400rwhp, a new oem clutch and new oem flywheel will work just fine. For a setup with a bit more holding power and heavier pedal pressure (i.e. slightly less 'comfortable' to drive), use a new oem clutch plate and a new oem flywheel with an aftermarket pressure plate (eg. RPS or ACT).

1) Agreed. In general, don't let Toyota work on your Mkiv TT. No disrespect intended, but their mechanics are experts at Camrys and 4-Runners (by necessity).
2) Based on the additional information you provided, it definitely sounds to me like the clutch pedal needs to be adjusted.
3) Yes, the clutch can simply be adjusted with a 12mm wrench - the nut is on the rod that connects the clutch pedal through the firewall to the clutch master cylinder. You can get to it by laying on the driver's side floor (you'll probably need a flashlight too). Just loosen the locknut and spin the shaft to adjust. Note: the switch on the clutch pedal to the start the car is not affected by adjusting the clutch master cylinder rod length.

OK thank you very much for the insight :bigthumb:

shortening the clutch line
 

Hey so I tried to shorting the clutch rod like you described, I got the nut unscrewed but I could not twist the part behind it, I tried using a 14mm wrench and it wouldnt budge but I didnt wanna keep trying and break it off so I just left it where it was.

You need to twist the small rod - it's only about 3/16ths thick... just spin it with your fingers.

haha ok that helps alot lol thanks

Ok so I did it and it didnt help at all so its either the clutch or flywheel, Il find out Thursday or Friday. I am also changing out all my oil in the engine, tranny, and diff, what would you suggest I get for these, along with what filter has worked best, I was always fond of K&N but I heard that they can sometime keep your oil pressure too low, Just let me know what you think, I was thinking about doing mobil 1 for the engine and royal purple for the tranny, and either of those two for the diff. I was going to put 10w30 in as well but the last dealership put 5w30 in, what are your thoughts on that. Thanks in advance

Engine oil, anything full synthetic (10W30 only!)
6spd: Royal Purple Synchromax
Diff: Redline Shockproof Heavy
Air filter: K&N
Oil filter: TRD (Purolator is okay)

update on the transmission problem
 

Ok so I found a toyota master mechanic that has experience with supras and the 6 speed. He said that there is a chance that either the dealership that I bought it from didnt put the clutch/pressure plate, they installed the flywheel improperly, a bad throwout bearing, as well as many other things or even it could even be the gear box because the metallic clunking noise I hear when I push in the clutch only happens when I am driving and not when I am sitting in neutral:crazy2: . So I told them to go ahead and take out the transmission, the mechanic was actually a really cool guy, and even when the service manager walked away the guy was really cool and helpful, not like any other lexus or toyota dealership ive ever worked with, the manager was really cool too! The guy before I even paid for anything or asked to pull the transmission, the mechanic was looking of gear boxes and transmissions, where he could get them from and how long it would take to get each one with a price, which was really cool. I decided to get the fidanza flywheel and am replacing the slave cylinder and master cylinder while im doing all this work too. Il give you an update on what my situation is as I get more info.

Are you sure you need a new clutch slave cylinder and master cylinder? It's very rare for either of those to go bad...

I cant remember which one the mechanic said but he said since he was taking out the tranny he suggested I might replace the slave cylinder, and he said if I look to get an aftermarket pressure plate or clutch that it would handle the extra pressure, so I would just get it out of the way now

First rule of maintenance - if it ain't broke, don't fix it. *shrug* To me, that's strike one against this 'mechanic'.

P.S. I've seen the mount point for the clutch fork get broken in the past, and could fit with your description of symptoms. This problem can be verified via the inspection port (i.e. without transmission removal).

Full dignosis
 

So what ended up being the problem were a few things, I needed a new drive shaft because i think the U joint was bent, so I got a stock replacement from horsepowerfreaks. The second was pressure plate failure, so I got the rps pressure plate. And then I am replacing the tail shaft seal because of seepage, and he said that there was something with the slave cylinder, i cant remember off the top of my head, but he suggested I replace it, and so thats why we were doing that. All in all its going to cost me between $2000 to $2500 with parts and labor, and I bought all the parts online, the mechanic was a big help. And hopefully if all the parts come in ontime I will have my car back running perfectly by Thrusday Friday next week!

I'm glad you got everything diagnosed. Seems like a lot of $ (I know 'yota labor isn't cheap). Also the problems you're describing are very, very rare (eg. mkiv TT driveshaft u-joints just don't bend - never seen this happen even at high boost with wheel hop - I've seen several driveshafts that look like licorice in the middle, but no bent u-joints). Although the problems are rare, it seems they did happen - to your Supra. Good luck with all of the repairs and I hope it all runs great when they're done.

Oh, and the bent u-joint doesn't fit with the symptoms you described above *shrug*.