shifts are not very firm

[DorianL]

My 200-4R has been operating quite smoothly yet the shifts are not very firm. In fact at WOT I can't feel them. However, if I raise the RPM in gear and let off the gas, the shift is firmer. It almost seems as if I have to let off the gas to get a firm shift.

I am going to take a while trying to figure this one out.

I rebuilt the trans myself last year. I have a few hardened parts in there. Some Alto performance frictions. The pump is a 13 vane with a high pressure regulator. The VB is from CK with a shift kit, as is the governor.

I have a PTS deep pan and pick up. I also have a PTS wide band with a used GN servo.

The converter is a TCI 3000 stall something-or-other.

I have a hughs TV cable adapter on my Holley carb.

The beast is a 4000 lbs malibu with 3.42 gears and a 500HP/550TQ small block.

Static, the pressures seem to check out.

What are the next steps to finding the problem and then fixing it?

Finally, today I finally installed a TCC circuit. Wow, what a difference. However, with the pan off I noticed that the oil smelled a bit toasty. It was not pink anymore but was browning - not sure if this is related to insufficient cooling or running around with no TCC on or the few blasts that I did that flared.

Need help!

D.

 

[DorianL]

BTW, I used to have a PTS kit in there and seem to recall I had a similar problem. But at that time, I had a stock VB in there.

I am using an external cooler by B&M.

 

[mikestertwo]

An inefficient converter will give you those symptoms. A lot of slippage at high torque loads.

 

[DorianL]

I have just a few hundred miles on the TCI Streetfighter 3000.

How can I check if this is the source of my woes?

Or, can this converter not survive behind this smallblock?

 

[DorianL]

Will post my pressures later today.

 

[turbo nasty]

You tried tightening the tv up a few clicks?

http://www.turbobuick.com/forums/transmission-talk/252905-toasty-transfluid.html

I see you posted about your fluid being burn smelling thats not a good sign, your trans could be smoked now. If you flare at WOT 2-3 times in say the 2-3 shift then it should be pulled and checked.
The directs are probably smoked

 

[mikestertwo]

I have just a few hundred miles on the TCI Streetfighter 3000.

How can I check if this is the source of my woes?

Or, can this converter not survive behind this smallblock?

All you can do is try another converter like a stock D5. Hi stall 12" converters usually are not very efficient and generate a lot of heat. If your fluid is already getting dark I would inspect the trans first before making any changes. JMHO :smile:

 

[DorianL]

Rats! I got a couple of races over on the 14th and the 21st.

I don't think I will have time to tear into this and replace clutches.

I'll tighten slightly the TV and check my pressures this evening and post.

The TC is a 10-inch.

Remember - this spare parts need to be shipped to Belgium.

 

[DorianL]

Hmmm - I was checking through my old posts. It seems like this problem has been around forever. My tranny fluid was ok with my stock converter. I think this high stall converter that started backing the transfluid.

Hmmmm

 

[Alky V6]

ATF will develop a different smell depending on the problem with the trans/converter. Burned friction elements have a different smell than fluid overheated by a torque converter. If you have a very fine film of black dust covering the bottom of your pan, it's time to replace frictions and figure out why they burned.

Fluid that has been badly overheated by the TC will sometimes burn the red dye out of the fluid. Usually the pan will be clean. The smell will be very unique and will fill the room. Very bad.

 

[Lee Thompson]

thank you

ATF will develop a different smell depending on the problem with the trans/converter. Burned friction elements have a different smell than fluid overheated by a torque converter. If you have a very fine film of black dust covering the bottom of your pan, it's time to replace frictions and figure out why they burned.

Fluid that has been badly overheated by the TC will sometimes burn the red dye out of the fluid. Usually the pan will be clean. The smell will be very unique and will fill the room. Very bad.

GOOD INFO !!!!!!!!

 

[DorianL]

The bottom of the pan looked clean. The smell is not that strong.

 

[Alky V6]

The bottom of the pan looked clean. The smell is not that strong.

I've seen blackened friction elements even with a clean pan.

 

[DorianL]

Well at this point I'm kinda (/)ssssssss> -ed

Will race it then tear into the trans.

I am fairly sure that the change in color is due to the high-stall TC not locking up.

However, it never shifted as firmly as I wanted. I will check my pressures tonight and report here.

BTW - under regular non-stomp driving, the trans works just fine.

 

[DorianL]

P - 80 - 240
R - 125 - 290
N - 80 - 240
D - 80 - 240
3 - 80 - 240
2 - 230 - 240
1 - 230 - 240

This is with a CK pressure regulator.

All at 1000 rpm

Going for a test drive now... see what that needle does.

 

[DorianL]

Well - here's what I got:
I held in 2, got 200 PSI, a very small blip of the needle right before it shifted 1 - 2 and I get a quick but soft shift.

I left in drive and tightened the TV and got the same 1 - 2 results with 150 PSI. A small blip, a fast shift, but nothing neck snapping.

 

[DorianL]

From what I understand. This is all perfect.

Rats, I guess there is no choice but to drop the trans and peer inside.

Seems like there is going to be quite a few toasted clutches.

Unless it could be something else? With this kind of pressure shouldn't the shifts be snappy as weel as fast?

 

[turbo nasty]

Do you have a large aux cooler for the trans? if no get the biggest one you can if using higher stall speeds

 

[DorianL]

That is all I am running.

 

[turbo nasty]

Looks good. Hope u get it straight.