jeromio

97 LT1 from a TA. After 165K mi, trans gave up. Got a rebuilt unit and rebuilt converter. Had the same case with integrated bell housing, altho "new" one didn't have the threaded holes for the dust cover (super annoying to discover this after installed so had to drill/tap holes under the vehicle).

Note, the TC has 1 quart of new fluid in it.

During install, everything lined up and bolted up fine, but the TC/Flexplate wouldn't turn (couldn't install TC bolts). Oops, too tight. Removed trans, hurky-jerked the TC a bit and it slid in another "clunk". At that point, everything was a lot looser, actually had to slide TC quite a bit towards the flexplate to bolt it. Started the engine, added 6qts (so total of 7qts), but the level wasn't going down, reading way over full. Ran it thru gears, backed it up a few feet, drove it forward. Still reading *way* past full.

Ok, so now I unbolted things, measured the space betw TC and flexplate - it was 5/16". Research says it should be betw 0.060" and 0.187". Not good. Ok, so got longer TC bolts and added spacers: 0.2" thick to get the space down to 0.1125 (1/16)". Bolted everything back, started up, level then read dry. This is good, right? So now I add a quart, now it reads low, add one more, now it's back to over full?!?

I took a chance and drove it around the block. Can't get past 30mph, but it seems to be fine, shifting thru to 3rd gear. Everything sounds good, shifts smooth.

Called trans rebuilder and he confirmed unit was dry as delivered. He says I must've pulled things together with bell housing bolts, run it, and burned out pump. This is not the case - learned this lesson the hard way 25 years ago.

I am *not* any kind of auto trans expert. I did have the boo-boo where the TC wasn't fully seated, but the engine was never turned over in that state. So no reason for the pump to be damaged. And if the pump *was* somehow damaged, I should not be able to get into gear or drive it at all, right?

But why is it over full with only 9 quarts?? Help?

wht/73

I think you have/had 2 problems.
1st the converter not all the way back and trans tightened. (Bad)
2nd not enough pump engagement and ran it that way.
I'm sure the pro's will correct me if I'm wrong.
I hope I am for your sake.
PS, I made the same mistake also 30yrs ago too!

PBA

Since its drives, the pump is working. If the transmission builder forgot the dipstick stop that bolts to the valve body it can read overfull. Do you have all four gears? Any delay when putting it into gear?

wht/73

See I told you the pro's would correct me!

jeromio

It drives well around the neighborhood. Shifts are nice and smooth - almost imperceptible. Haven't had the courage to take it on the highway to get it into 4th gear yet.

I did consider the dipstick to be "faulty" - but it seems like it's in at least close enough - and its tab does bolt to the one bell housing bolt. But when I say it's reading over full, I mean like, it's a good 2 inches past the top mark on the dipstick. Right at the "K" in "Park".

I like the confirmation that the pump must be working. But like I said, this is such a mystery. It should be 2 quarts low.

jeromio

Ok. I have some more info. I bought a pressure sender (and gauge, but gauge has yet to arrive.

When I removed the plug, a tiny bit of fluid dripped out - not sure if that's normal.

Afterwards (back level), I checked the dipstick w/ the engine running in Park. It was right at the top of "Warm"? Which is good but weird, so I checked 4 more times. Could it be that there was some air bubble or something, and removing that plug cured it? Or I'm just crazy? Both?

I hooked an ohm-meter to the gauge and got 40 at idle (park or drive) which my calcs (10-180ohm range, 400psi sender) gets me 66.6psi. If I goose the throttle, it goes to 70 or 80 (little goose, big goose) which would be 133psi and 155psi respectively. So, within normal ranges. Drove around the block and it pretty much rev matches in the range 40ohm to 50ohm - stepping on it (dangerous to do in n'hood bc LT1) it jumps to 80 or 90ohm. Confirms the pump is working. Still haven't gone on highway to confirm 4th, but I'm certain it will happily shift there. I guess I just need to bite the bullet and try it.

Can't really say I've solved the mystery. I mean, it should take another 2qts of fluid, but according to dipstick it's full - but at least not overfull?

Also, in case someone wonders - no it's not leaking any fluid.

wht/73

Get one of these. $37

jeromio

I basically have one - permanently installed tho.

wht/73

Ok,
Is your car higher up in the rear or is it level?
just remember, fluid seeks its own level.
So if your car/trans sits somewhat level, that's where it is.
My Nova sits stink bug'ish so I pull it up on to the apron of the garage to check the level.

jeromio

Yeah, I've been measuring w/ the vehicle level.

Mostly I'm worried that there's something fishy with the trans. I'm in NYC, bought the trans from a rebuilder in PA, 2 hrs away. He warranties it for 3 yrs. But I'd pretty much have to risk driving 2hrs to even get him to check it out.

mrvedit

If the builder supplied the trans "dry", really dry, it and the converter would take about 12 quarts to fill. However, some trans shops dyno test the trans and they drain it, but that still leaves a few quarts in it.

Here are my suggestions:
1. Pump out the ATF through the dipstick tube using a cheap hand pump. (About $12 at any auto parts store or less at HF.)
2. Drop the pan.
3. Tell us how much ATF you pumped out plus how much was in the pan. Should be about 4-5 quarts with the stock shallow pan
4. Insert the dip stick and check where the "Hot Full" line is in regard to the trans case - it should be a little above the mating surface of the pan.
5. Check that the filter fits snuggly into the pump.

Perhaps you will find too much or too little fluid in the trans or something obvious will reveal itself.

jeromio

Yeah, you're right. That is what I need to do. Just really hate the idea of cracking open the trans (and also dealing w/ all that fluid).

mrvedit

Pumping most of the fluid out through the dipstick tube makes the task much cleaner.
Else the fluid is over is over the top of the pan and makes a big mess.
A 2' by 3' cement mixing tub from Lowes or HomeDepot will catch most any automotive fluid "project" and costs only about $12.

wht/73

Good tip!

Thanks!

Mike Pason

I just bought a tranny from that guy and i think i got fucked on the tranny slips and carrys on