Ive been wrapping up a 72 Camaro build and trying to dial everything in. Its an all around car w stiff suspension , big brakes, etc,etc.... not a drag car.
It has an LS3 crate engine w a small custom cam, GMPP dual plane intake and Fast EZ efi, 2004R trans w a 2200 rpm stall, 3.42 gears.
I took it to the dragstrip to dial in the timing curve on the MSD box yesterday. First pass was a 12.15 at 112, which was OK, but 3-5 mph slower than I expected. After the first pass I knocked it in neutral while I coasted down the return lane and when I put it back in gear ,it slipped badly then caught. I down shifted to 3rd and the same thing ,and second too. Only when I downshifted to first did it catch. I let it cool down about 15 mins and took it for a test run back down the return lane. It shifted OK, so I chalked it up as a fluke and went back out for another pass. The pass was a throw away because it spun pretty bad, but I stayed in it anyway. By the time I hit second gear there was a loud shrieking sound and the same into 3rd. I stopped at the timing shack to get my time slip and the lady said the line tech saw a slight trans leak. I didn't want to bugger the track up for the bracket race later ,so I called it a day.
I drove the car home ( a 40 mile drive ) and it ran fine at part throttle. I could smell trans fluid when I stopped but the leak was very minor. At one of the stops I kicked it and the car went through the RPMs in first and second quickly, but shifted hard. Like it was slipping some ,but still hammering the next gear.
Anyone have a clue as to what is going on. I haven't jacked the car up yet, but it looks like the leak is around the dipstick/trans line area. Thanks in advance for your insight.

 

If it's leaking, it could be low on fluid, causing it to slip. Find the leak, but ch.ances are you already damaged friction material.

 

Thanks for the response. I was running a half quart over full at the recommendation of the outfit that built it. I checked the fluid and it is still at or above full.
Would the shrieking noise be slippage of the friction material? In regular driving the trans acts normal. The only time I felt a pronounced slip was the coasting down the return lane deal. It felt like slipping the clutch in a manual trans.

EDIT.....I just checked the fluid level for the first time after the 40 mile ride home. It is showing a half quart low. That would be a full quart below where I run it. looks like the leak blew 1/2 quart on the ride home and a 1/2 quart at the track, I guess. I didn't smell any fluid burning or have any indication of a leak when I got to the track.

 

Just me thinking out loud here and i very well could be wrong, but i thought you needed to upgrade certain components in the 2004R before you could use neutral on the top end as a coast? The internals are spinning extremely fast at the top of the strip.

 

It was just on the return lane that I coasted. Might have been going 35 MPH. But thanks for trying to help me figure this thing out. More input, please.

 

Shifting to neutral at high speed is a bad idea with any auto trans.

 

Good advice. What do you think my shrieking sound is? I can down load the vid of my second run if it would help figure it out. My better run is on the carbed LSX forum under " problem fixed ". I didn't notice it on the first run, but you can hear it through first gear in the vid.

 

It's probably going to require removal due to damage from slipping. I would get it out, apart, and see what's going on, instead of guessing at it.

 

Ive pretty much resolved to that at this point . I didn't want to pull the trans if there was a test to do to maybe verify what the problem may be.
Is there a book or video that shows step by step how to build a performance 2004R trans?
Is there a way to know if the converter is up to the task, or should I look into a converter that is known to handle 500+ hp and 500 ft lbs?

 

Any shrieking noise is likely to be a major problem. Pump, converter, band delaminated, planetary, torrington bearing, etc.
It could be a driveline issue, and if you have a way to look at it under load (chassis dyno) you may be able to isolate it. Otherwise get the car off the ground, look at it all, and get the transmission out.

CKPerformance sells a book for performance builds.

The 200-4R is not a unit I would recommend for a novice builder.

 

Yep, it looks like it time to drop the trans. After doing some research this morning, im not going to tackle a 2004R build. Time to come up with a new plan. Thanks for the help.

 

I just jacked the car up to find the leak source and its not from the usual places. Not the dipstick tube, lines, or TV cable. It looks like its coming from the front "pump?" gasket or maybe a hairline clack in the converter? There is no detectable "wetness " around the front seal, just from an inch or so above the trans pan mating surface, down. And just up front close to the converter. What do you all make of that?

 

Before you pull it, clean it off with a degreasing cleaner and dust it with talcum powder or do a UV-visible dye in the fluid so you can find the leak origin.

If that fails, pull it and see if you can find the leak up front by pulling the pump.

 

That's a good idea. I just went back out there and numbered around the converter and had my son bump it over while I inspected it. I couldn't see anything that looked like a leak source. I will spray it down with carb cleaner and talc it up, top off the fluid and crank it up on jackstands, and crawl under it to see whats going on. I will report back shortly. Thanks

 

Its going take more load than I can give on jack stands to make it leak, I guess. I idled it in gear, then had my son hold the brake and pull up against the converter at 1500 rpms and 2500 rpms. No leaks showed up. I did hear a knocking, clunking noise when it first cranked that sounded like it came from the trans or converter. It went away after a minute or so. Ive heard the noise before but thought it was a lean popping from the exhaust when it first cranked, but like I said, it sounds trans related from under the car.

 

I think my problem is in the converter. I was able to get the shrieking noise to show back up while on the jack stands and using the ol rubber hose stethoscope found that it is in the converter. If I don't have any metal in the pan, Im going to try a new converter. I think the leak is from the front seal. Im going to pull the pan and check for metal and go from there.

 

Be careful,
all the metal from that converter will go back through the pump on it's way to the cooler.
I would cut the converter apart and see what failed. If there is any metal debris, the trans will need to be opened up and that cleaned out.
BTDT. Good luck.

 

Thanks for the advise. I will do just that. Ive never cut a converter open, but there is a first time for everything, lol.
I want to understand exactly what you are saying. If the part of the converter that failed is metal and there are fragments in the converter, disassemble and clean the trans, cooler and lines ?

 

Take it to a converter shop and have it cut open. Or at least drain it into a paper towel or paint filter and see what debris comes out.

 

I have a box full of paint filters from my last paint job, so I will drain it into a double stack and see what shows up. Thanks again !