ss1le02

iTrader: (4)

So if I take the car to redline on a freeway entrance ramp, it is getting almost impossible to shift from 3rd to 4th and so on. The car is a 2002 SS with an LS7 clutch set up, newer OEM master cylinder and throwout bearing. I've bled it using the Mighty Vac many times. No bubbles come up when using the Mighty Vac. The clutch has maybe 7000 miles on it and the master cylinder/throwout bearing maybe 4000 miles. The problem seems to be progressively getting worse. BTW, the clutch has been in for about 2 years with no runs at the dradstrip on it. It has always done this a little since I put the heads/cam on it about 4 years ago, but now it's getting really bad. Why is it getting worse? Any theories anybody?

Honda Nick

iTrader: (1)

The factory hydraulics suck, plus you're probably cooking your fluid. Have you thought about a Tick Master Cylinder?

SPEC-01

iTrader: (2)

The OP mentioned having bled the system repetatively without getting air to pass which would typically support his beleif that this isn't hydraulic. Of course as mentioned above these cars have notoriously poor hydraulic systems. If he were boiling the fluid he could check the reservior and if the fluid inside were dark, cloudy or discolored then it could be assumed that he needs to flush and refill the system. Assuming that he has already done this through the course of bleeding though I understand why he feels that this isn't likely.

All that being said...what does the pedal feel like? How does the car shift otherwise? Where does engagement occur relative to clutch pedal travel? Let me know and I will be happy to assist you further. Thanks!

ss1le02

iTrader: (4)

As you mentioned in your first paragraph, I'm well aware of the shortcomings of the f-body hydraulic clutch set up. Before and after new LS7 clutch was put in the system was bled entirely. I could start up the car with it sitting for days, ie. cold as can be, and power shift through the gears with the problem still present. Thus the boiling hydraulic fluid isn't an issue.

As far as engagement goes, with the LS7 clutch it is much sooner than the stock clutch set up was. Pedal feel seems to be a little harder in the last 6 months on initial start up after the car has cooled down, say overnight.

It seems to be normal, other than flooring it, and trying to shift quick. It shifts fine under normal driving. Could the LS7 clutch already be going bad?

SPEC-01

iTrader: (2)

I figured you knew the basics and subsequently that you would have checked them before posting...especially since you had been bleeding the system. Since the car shifts fine in normal driving we know that the clutch is releasing. In the OP you reference this affecting 3-4 shifts specifically. Does this also occur the same way for all other gears? If not this is most likely an internal transmission issue.

If it affects all gears then you may have an issue with the disc or plate. For instance if the disc were bent it could cause difficulty on shifting. This would be more noticible when shifting quickly than when shifting slowing which would allow the synchro's to work better. It could also be an issue with the SAC-type (Self-Adjusting Cover) that the oe LS7 uses. If the SAC mechanism was hung-up, the plate wouldn't fully actuate. Most times this affects all shifts no matter what the speed but it is possible that the plate is responding slower than it should (effectively being lazy) and this would be made more evident when shifting fast.

I know you probably don't want to hear this but the only way to check it out is to pull the parts. If you do, please post some pics so I can better assist you in troubleshooting! As always I am happy to help...so let me know if you have any further questions. Thanks!

ss1le02

iTrader: (4)

1-2 shift is fine, 2-3 is harder, 3-4 hard, 5-6 really hard to get in gear.

I blew up the 3-4 synchro a few years ago on a shift. I had my friend(mechanic for Doug Rippie Motorsports) rebuild it. He replaced the broken/worn parts, and we upgraded the 3-4 fork. At this point I put in the LS7 clutch. Everything worked fine until about a year and a half ago. It was hard to get it into all gears during all types of shifting. I drove it that way until the end of the summer. I then tried a new OEM master cylinder. That didn't help. At that point it became clear that I had to pull the tranny to find out what's wrong. The problem turned out to be a bad pilot bushing. When I pulled the clutch off needle bearings fell out. I replaced that along with a new OEM throwout bearing. This worked fine until a few months ago when I noticed a stiff pedal on initial start up, then the shifting getting progressively harder on high RPM shifts as time goes on.

Since I bought an extra OEM master cylinder awhile ago, can I do the DIY mod to make it adjustable, or is a Tick/Mcleod the way to go?

rabiddog

iTrader: (1)

tick/mcloed and I think spec all have adjustables. no DIY mod. sounds like a internal issue. I am guessing your going to have another rebuild coming soon.

SPEC-01

iTrader: (2)

You can try an adjustable master as it may help iof this is an issue associated with needing more throw. Of course, if it is an internal issue the adjustable master won't help. It's easier and quicker to install an adjustable master but if it doesn't make a difference then it sounds like you may need to tear down the trans. We do offer an adjustable master that is based on the OE unit for $175. Let me know if you need one and I will be happy to assist you. Thanks,