Let me start with a little background information. I have a 68 camaro with a 454 and a tremec 5 speed. I put in a Tremec 3550 in 2000. The car drove great and shifting was perfect. I had a ford 9 inch rear with a 3:89 posi and 28 spline axles. Well, over time the rear was starting to take a bit of a beating so I swapped in a Currie 9 inch with a detroit locker and 35 spline axles. I also installed a set of Southside Lift bars. I made NO OTHER CHANGES. The following day while driving the car I noticed that is was progressively starting to shift worse and worse. I hadn't been driving it hard but had made one pull through all gears. I called Currie and confirmed that the pinion angle was set to factory specs and I rechecked just to be sure. All appeared correct.

At this point the car crunches into second gear when shifted normally. If you go extra slow you can feel it clunk inside then go into grear. This is the only way to shift 1 -2 without grinding. All other gears ok. Over the next 2 months these are the changes that I made.

1) Replaced clutch and pressure plate. I removed an 11 inch diaphram type and installed an 11 inch borg and beck pressure plate. Set clutch release clearance to .040. Road tested car, no change.

2) Removed trans again and replaced brass blocker rings for all gears and filled with GM Syncromesh. Road tested car, no change.

3) Replaced complete transmission with new Tremec TKO2. Road tested car, no change.

4) Unbolted front of lift bars incase rear suspension was binding causing incorrect pinion angle. No change

At this point I'm starting to get a little tweeked. I'm $2600 in the hole trying to get the car to shift right after installing a $2500 rear diff, and the car drives like crap. Here are some things that I now for sure:

1) The clutch is releasing completely. I can physically check it with a feeler guage and with the car running but not moving, I can shift in and out of reverse without grinding. This is after using a forward gear before going into reverse for the first time.

2) The clutch pedal is utilizing its full range of travel and the release bearing has aprox 1/4 inch freeplay. I even drilled a hole lower in the upper arm of the z-bar for even more travel.

3) I never changed the release fork. I did however try installing an adjustable pivot ball, which made no difference. I also tried a stock, a medium, and a tall release bearing. At this time I have the medium in. None made a difference.

I would love for someone to help me with this problem. It really has me stumped. In fact, 4 years ago I bought a 70 chevelle and have mostly driven it because the camaro just isn't that fun anymore and I'm not going to keep throwing parts it. Any help would be great. If we can't get this figured out, I gonna put a 4 speed back in this car and hope for the best.

when car is sitting on ground how much clearance from yolk of driveshaft to the seal. maybe it is sticking out to far or in to far and pushing on rear shaft of tranny.just a thought.

Great suggestion. This is exactly the kind of thing I'm looking for. I have checked and there is a good fit with no binding. It's a Denny's shaft and the fit is excellent. Tomorrow I will certainly check again. I have a drive on lift at my shop. Thanks again, and keep the ideas coming.

What's the torque limit on the Tremac 3550?

A healthy BB may just be too much regardless.

Otherwise, donno??

pdq67

hmmm, you swapped one 9" for another, and everything went to he!!...
You replaced everything forward of the driveshaft with no change.

It's hard to shift.

I just went thru something similar with my TKO. It shifted beutiful last year. This winter I replaced the rear axle and the driveshaft, and when I put the car on the road it was VERY hard to get it in gear when stopped, particularly first. The only thing I did to the trans was change from GM syncromesh to amsiol synthetic.

The problem turned out to be that the trans to bellhousing bolts has loosened up, in fact 2 had fallen out. This caused enough misalignment on the input and mainshaft to have a horrible effect on shifting.

I doubt you got any bolts loose, but I'm wondering if your bellhousing is dialed in to the recommened .005" max runout, and also if your pilot bearing is good?

Did you dail in the bell when you first put the trans in?
Did you recheck it when you changed the clutch?

I thought I read somewhere that the TKO does not like spools or lockers for street. Anybody else read or hear of this?

Jim, bolts loose? Will be pulling again soon for PM.

Thanks for the suggestions. To answer your questions, the TKO2 is rated for 500 lb/ft. I tried replacing the bronze pilot bushing with a roller bearing and dialed in the bell housing to .003. This changed nothing. I have suspected that the locker is the route of the problem, but many people, even ones on this forum, say that it's impossible. I know there are others here that have tremecs and lockers. What do your trannies shift like? I had imagined that erratic driveshaft rotation caused by the locker was causing synco issues but the shifting is still poor when driving in a straight line.

The Locker could be the problem. I have a Lock Right in my truck and when I try to shift into second while making a turn it does the same thing. Mine only does it when turning, but the locker is what causes it. I have a T5 Borg Warner, but your transmission might be more sensitive than others. I can't explain exactly why this happens, but I think it has something to do with the way the teeth engauge in the locker and then unload when the pressure it taken off when the clutch in disengauged.

What I suspect, is that the big ratio drop from first to second (3.27 - 1.98) causes the lockers effect to be more dramatic in the tremec causing it to be apparent nearly all the time. Thanks for the help Freddie. I see you deal in drivetrain parts, do you know of anyone that makes a 35 spline posi for a 9 inch? I'm not sure if its even possible due to the design features of the 9 inch.

I feel your pain!
One thing I might have tried is putting the old rear back in just for a road test. That would tell for sure if the rear is the problem.

a buddy of mine had same setup and replaced the locker with a detroit trutrac and problem went away.

I had a locker and TKO, shifted awesome. However, I may have been lucky, so I recommend pursuing that idea further.

Jody

The Detroit Locker is the only one that I know of for 35 spline axles.

Here's a question that I think I already know the answer to. In an effort to utilize my 35 spline axles, does anyone think that I could get away with installing a spool to fix this problem? I know they don't belong on the street but I have a few cars, so if rain is eminent I could keep this one in the garage. I know that tight turns at slow speeds are tough, but they are with the Detroit and I'm use to it? Also the car just runs a regular radial tire, nothing stickey. Some people say spools on the street are fine, others say NO WAY. There aren't many that haven't taken a stand on one side or the other. What do you guys think?

I'm against it myself. The reason is that I have seen too many broken parts with spools on the street. I have seen all of the studs sheered off of the axle, broken axles and other broken parts. If you loose all of the studs while you are driving down the road and the wheel comes off you might just damage your car, or you might kill someone in the car in other lane when you hit them head on. Maybe I'm just looking too far on the bad side, but it scares me.