psu_Crash Posted September 5, 2015 Report Share Posted September 5, 2015 So as some of you have read I've had some issues with transmissions this summer. The car hasn't really been driven accept at autocross events, but when it is driven normally on the road it's fine. So the transmission that I swapped in a month or so ago doesn't like to go into second gear. Somewhat randomly... It's fine for the first few hard launches at an event, then after that second gear isn't an option after even a mediocre launch. It doesn't grind it just doesn't go, even though the shifter is roughly in position where it should be in second. I have found that if I ease it off the line and then grab second it's A OK, just don't grab third and expect to get back in second. Any launch over aprox 3.5k though and second isn't an option for the entire lap. Even after letting revs fall, double clutching, rev matching ... etc. The second I leave the auto-x course I can get in back in second no problem when shifting easy. To recap:The first (original) tranny that I took out had a linkage issue at an event early this year where I jammed it into first going way to fast. Squawked the tires and thought oops... then coming out of the corner it wouldn't come out of first so I pulled hard. Shifter cam out of first but the tranny was stuck in first. Tearing that down revealed a little where on the shifter arm and it was aparently stuck outside of the U shaped gear selectors on the end of the shift rods. Once I freed that up everything seemed to shift fine on the bench. But, since I had a spare tranny (of unknown condition) I swapped that in and then have had the problem I described above. Master and slave seem to be just fine and adjusted well. I get plenty of fork travel. I have always used Redline MT-90 oil with no problems. The only thing I did different this time was add a couple ounces of NMF, the anti-friction stuff that Joe (4CylFury) runs in his engine according to the directions. No idea if that could be a factor here.So I just drained the oil from the current tranny and nothing really out of the ordinary. Silverish/gray sludge on the drain plug a little more than expected from a tranny I just cleaned out and filled with fresh oil, but nothing crazy. So my question is, do I try and refill the current tranny and hope the issue goes away (doubtful), throw the first tranny back in that never had an issue aside from user error, or drop in a third tranny I have here that is also unknown condition. None of them have more linkage slop or shaft play than the others. Although apparently something is going on with the current install. I really don't want to swap transmissions again this weekend even though I am 100% prepared to! Sorry about the long winded post, I just want to get all the info out there that I can!Any advice, suggestions or criticisms are appreciated Link to comment Share on other sites More sharing options...
psu_Crash Posted September 5, 2015 Author Report Share Posted September 5, 2015 (edited) Just dropped the pan and it was full of sparkly gray oil, way more so than my stock 80k miles trans had when I pulled it. Entire bottom of the pan had a thick layer of the stuff. Doesn't seem very good for a tranny with 50ish miles on it since a good cleaning and fresh oil. Could be the synthetic just cleaned out a lot of the old crap though I suppose. Edited September 5, 2015 by psu_Crash Link to comment Share on other sites More sharing options...
DieHARDmitsu. Posted September 5, 2015 Report Share Posted September 5, 2015 MT90 seems to cause a lot of issues in trans that require gl4. I would suggest using the GL4 stuff... keep fingers crossed.Your car makes good low end torque with the HX35, that itself will stress the drivetrain especially in the lower gears used for X-ing. Link to comment Share on other sites More sharing options...
taeisallin Posted September 5, 2015 Report Share Posted September 5, 2015 i say give the third tranny a shot. if not, we'll look for another one for ya 1 Link to comment Share on other sites More sharing options...
stariondreams Posted September 5, 2015 Report Share Posted September 5, 2015 I always wondered what makes the stock transmission weak besides the tin pans. I read some time ago something about the case. i have never cracke one open to look. There has to be a way to improve Link to comment Share on other sites More sharing options...
psu_Crash Posted September 5, 2015 Author Report Share Posted September 5, 2015 3 transmissions in as many months after 16 hard years on the first (in my hands).. I guess I have to Link to comment Share on other sites More sharing options...
psu_Crash Posted September 5, 2015 Author Report Share Posted September 5, 2015 Btw I run a tuff pan and have since they existed Link to comment Share on other sites More sharing options...
ucw458 Posted September 5, 2015 Report Share Posted September 5, 2015 Are you running poly engine mounts and a poly trans mount? If you are I would suggest putting in a stock trans mount. Having all your mounts be rock hard poly can cause trans case flex. Flexing the case can cause issues and failures. I've heard stories from drag racers talking about having solid mounts flexing the trans case when the frame twists and causing failures. Not saying this is your issue but it's something to look into. Then again maybe you just lucked out and had a few bad transmissions. If you haven't already I would look into having a shop completely rebuild a stock trans. I see so many people, not just SQ people, dump $ into the motor and ignore the rest of the drivetrain until it breaks. Anyone looking to add 300+ hp to any car should look into rebuilding or upgrading the rest of the drivetrain. I know that can add significant cost but it helps prevent tow truck rides. Link to comment Share on other sites More sharing options...
psu_Crash Posted September 5, 2015 Author Report Share Posted September 5, 2015 I did install a poly trans mount with the second transmission and ive been running a poly engine mount for years. Link to comment Share on other sites More sharing options...
psu_Crash Posted September 5, 2015 Author Report Share Posted September 5, 2015 MT90 seems to cause a lot of issues in trans that require gl4. I would suggest using the GL4 stuff... keep fingers crossed.Your car makes good low end torque with the HX35, that itself will stress the drivetrain especially in the lower gears used for X-ing. MT-90 is specifically rated GL-4. That's why I use it. I don't believe that's the issue since I've used it for 10 years in the old tranny with zero issues. The poly mounts and flex has me wondering though. May put a stock tranny mount back in an see if that changes anything. Link to comment Share on other sites More sharing options...
psu_Crash Posted September 8, 2015 Author Report Share Posted September 8, 2015 Dropped the tranny and planned to use the best linkage out of my spares then put that on the original and reinstall. Turns out my original tranny had the best parts of the three. Shift arm on the other 2 showed significant wear. With the amount of metal flake that I drained out of the problem tranny I sure don't trust anything about it. Everything is back together now aside from the exhaust. Tomorrow I'll get that in and do some test runs. If I still have issues then the plan is to change mounts. Link to comment Share on other sites More sharing options...
importwarrior Posted September 8, 2015 Report Share Posted September 8, 2015 hope it works well for you. a lot of work pulling replacing transmissions... Link to comment Share on other sites More sharing options...
Funky Phil Posted September 8, 2015 Report Share Posted September 8, 2015 so you added EMF this time? If your locked out, your gears arent slowing at all. Friction is how a synchro works. Link to comment Share on other sites More sharing options...
psu_Crash Posted September 8, 2015 Author Report Share Posted September 8, 2015 No additive this time around.Looks like no testing tonight because my garage has my rear wheels putting new sneakers on. Link to comment Share on other sites More sharing options...
psu_Crash Posted September 10, 2015 Author Report Share Posted September 10, 2015 Test run complete. I took a half dozen hard pulls from a dead stop then cruised a bit in between. All seems well so far! Shifter feels a little more notchy than it did but no issues getting it into gear at all. Link to comment Share on other sites More sharing options...
psu_Crash Posted October 9, 2015 Author Report Share Posted October 9, 2015 Update, I've done 2 autocross events since the trans install and all has been well! Once I get in second I stay there and that seems to work. The only issue now is getting into boost at the low RPMs I see in second. I rarely peak over 4k RPM in a lap. Solution may be a smaller turbo ... or 3.90 rear end. I'd change out the rear gears this weekend if I though it would still be streetable ... research is needed... Link to comment Share on other sites More sharing options...
Funky Phil Posted October 9, 2015 Report Share Posted October 9, 2015 If i wasnt constantly at TX highway speeds Id be using 3.90's. Link to comment Share on other sites More sharing options...
ucw458 Posted October 9, 2015 Report Share Posted October 9, 2015 3.90 gears are streetable but you will loose some hwy mpg by running them. Try an antilag setup for autocross runs. Shouldn't hurt anything for short duration runs. Or keep your foot on the gas while using the brakes. Link to comment Share on other sites More sharing options...
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