TC Clutch slipping?

[turbojimmy]

I checked the archives and couldn't find anything substantial. This is a follow-up question to a thread I hijacked in another section. In that thread, about a PT-61 turbo, the conversation turned to converters. The topic of RPM through the 1/4 came up and I posted a chart (because I'm a geek). The chart takes 2 Directscan recordings and plots MPH and RPM. In the chart I show various events from the DS log like shift points and TCC lockup.

The chart is here:
http://turbojimmy.4t.com/060604-2.htm

On the bottom left of the screen you can select Chart 3, Chart 2 or the Directscan data for each chart.

On each run the ECM calls for a TC lockup at 92 MPH. You can see it in the data. At 92 MPH, in 3rd gear, with 27" tires and a stock 3.42 rear, RPM should drop to around 4,000 RPM with a locked converter. The RPMs are not dropping at all really. The runs were recorded when the converter was new, trans is definitely not slipping (just had it apart actually and it looks fine inside).

On the street I can feel the converter lock up just fine.

Any ideas? I've been struggling to get faster than 115 MPH for a year-and-a-half now and I just can't do it. More boost, more timing, etc. - nothing helps. Now I'm starting to think I'm just running out of steam because I'm operating well beyond the peak RPM range. I just had the converter out of it, too. I wish I had thought of all this last week.

TIA,
Jim

 

[azgn]

if this is a 9/11 converter, there have been problems with locking at WOT, particularly the higher stall versions

 

[turbojimmy]

if this is a 9/11 converter, there have been problems with locking at WOT, particularly the higher stall versions

After all that typing I didn't say what kind of converter it is. It is indeed a 9/11 3400 stall. <sigh> I really don't feel like taking the trans back out.

By 'problems locking' do we mean slipping or just not locking at all? I guess it doesn't really matter, either way it doesn't work.

Thanks for the reply,
Jim

 

[azgn]

not locking at all........once locked, it is unlikely to slip

 

[turbojimmy]

not locking at all........once locked, it is unlikely to slip

Do you (or anyone) know what causes this? Can it be fixed? Does locking it earlier help? The runs I graphed were the first ones with that converter. Thus, I don't think it's ever locked. As I think back, I remember a real kick in the pants when my 10.5" locked. I don't get it with this 9/11. Now it all makes sense....just needed a few pieces of info to come together.

Thanks Woody (and Razor, too, for pointing it out in the first place)!

Jim

 

[azgn]

I would send it back to wherever you bought it.........

 

[Bens87tr]

Have you tried locking it 10 MPH or so sooner? Might try that because you would be locking it earlier in the powerband. Just something you could try before having to take it out.

 

[turbojimmy]

Have you tried locking it 10 MPH or so sooner? Might try that because you would be locking it earlier in the powerband. Just something you could try before having to take it out.

No I haven't. I didn't even suspect it wasn't locking until now. I have very little experience with locking the converter at the track. I got an Extender chip around the same time as the converter that allowed me to lock the converter. It was locking just driving around town, soI I just assumed it was locking at WOT because the chip told it to. I might just wire up a switch and lock it manually at different MPHs. If I can nurse it through the year I'll take it out while the car is hibernating for the winter.

Jim

 

[azgn]

definitely lock it with a switch.......most chips will not lock it at WOT unless specifically programmed to do so...

it will not lock until you are in 3rd gear in any case

 

[turbojimmy]

definitely lock it with a switch.......most chips will not lock it at WOT unless specifically programmed to do so...

it will not lock until you are in 3rd gear in any case

I can program the Extender to lock at a predetermined MPH. Normally I'd suspect the chip simply isn't trying to lock the converter, but I can see it calling for the lockup at the preset MPH using Directscan.

I like the idea of a switch so I can goof around with it myself.

Jim

 

[Bens87tr]

As far as I know the extender won't tell it to lock unless it's programmed too. You can set the MPH, I forget which combo you have to use (A/C, gear, etc) to get into that programming mode. My car liked around 76 or so MPH the fw times I tried it at the track. Get a switch for now to test it though.

 

[turbojimmy]

As far as I know the extender won't tell it to lock unless it's programmed too. You can set the MPH, I forget which combo you have to use (A/C, gear, etc) to get into that programming mode. My car liked around 76 or so MPH the fw times I tried it at the track. Get a switch for now to test it though.

The default is to NOT lock. I was locking at 92 MPH though I don't remember why. Again, normally I'd suspect operator error (as in I f'd up the programming), but you can see it calling for the TCC lockup at exactly 92 MPH in both runs.

What's interesting, to me anyway, is another set of DS files from a frustrating track rental day at Atco in September of last year. On my first run I had the Extender set to lock at 84 MPH. You can see the ECM call for the lock, but nothing happens. Then I switched to a Turbotweak chip that locks at 92 MPH (actually I think the June runs in question were also with a Turbotweak chip, not the Extender). Again, you can see it calling for the lockup and nothing happening. Then I put the Extender back in but forgot to program it so there was no call for lockup. The RPM at the same MPH (84 and 92) is exactly the same as the 'lockup' runs. So, it pretty much confirms the converter isn't locking despite being told to.

Had I known more about what to expect with a WOT lockup I would have realized in June of last year that my new converter was bad. Now it's not so new. If I do have it fixed I may have it restalled down to 3200 to keep my RPMs down a little at the track.

Jim

 

[turbojimmy]

I had to install a new shifter cable today so while I was in there I wired up a TCC lock switch to my ashtray swtich plate. Then I went out on Rt. 80 to 'test' it.

It's tough because by the time the car shifts to 3rd I'm already above the 65 MPH speed limit. I tried some 2nd gear lock ups, too. Bottom line is the more I'm into the throttle the sloppier the TC engagement is. I couldn't duplicate a non-lockup situation, though, but I wasn't going 84 or 92 MPH either. The fastest I tried to lock it at WOT was 75 MPH and it locked, but sloppily (slipped first).

So there's my unscientific results. I think maybe at the track if I lock it earlier that I can get it to lock up. Still shouldn't be slipping though.

Jim

 

[2quiktocare]

To my knowledge we have had only one of our 9X11's with a lock up issue, that being Woody's. We have many people running 10's and 9's with full lock and no issues at all. Not saying that may be an issue or not, but it may also have other issues that this is showing as a symptom rather than the actual problem.

 

[turbojimmy]

To my knowledge we have had only one of our 9X11's with a lock up issue, that being Woody's. We have many people running 10's and 9's with full lock and no issues at all. Not saying that may be an issue or not, but it may also have other issues that this is showing as a symptom rather than the actual problem.

Could be, but when I had a ProTorque 10.5" converter in it the lock-up was like a kick in the pants. I didn't know enough about how they work to realize there was a problem with this 9/11. It's a lot more loose than the ProTorque so I figured the lockup was the way it should be.

I just had the trans apart to replace the forward drum. All of the clutches and band looked brand new. I can't imagine what would be slipping.

Jim

 

[turbojimmy]

but it may also have other issues that this is showing as a symptom rather than the actual problem.

I'm also kind of curious as to what you think it might be a symptom of. If it's not the TC, and a symptom of some other problem, what might that problem be? I'm just curious, that's all. The trans works fine otherwise, shifts fine, downshifts fine, no slippage in any gear. It only slips when I try to lock the TC and even then it's not gear slippage per se, just the TC trying to lock.

Jim

 

[2quiktocare]

First check to make sure the brake pedal is adjusted correctly. Sometimes the switch gets bumped and will cause the switch to cancel lock up. Also a possibility of the TCC solenoid being either sluggish or non op. May also have something clogging the valving for the TCC.

 

[turbojimmy]

First check to make sure the brake pedal is adjusted correctly. Sometimes the switch gets bumped and will cause the switch to cancel lock up. Also a possibility of the TCC solenoid being either sluggish or non op. May also have something clogging the valving for the TCC.

There's no cancel in the DS logs. The TCC solenoid is new. Not sure how to check the valving - it locks fine except under heavy loads. At part throttle it locks hard - like a 1-2 shift. I don't think there's really much else to suspect other than the converter.

It's not a big deal. The 9/11s have a great reputation, they can't all be perfect.

Jim

 

[RICHIE HIGH PSI]

I have 2 of these converters, the tighter of the 2 i can lock up at wot, but the looser one(the one i need) will not lock at wot.
So it is not an issue with the tranny, it is with the converters.

Richie

 

[turbojimmy]

I have 2 of these converters, the tighter of the 2 i can lock up at wot, but the looser one(the one i need) will not lock at wot.
So it is not an issue with the tranny, it is with the converters.

Richie

How tight is tight and how loose is loose? I might have mine tightened up to around 3200 vs. the 3400 I'm at now. Would it do me any good?

Or should I abandon the 9/11 altogether and get something else (recommendations?)?

Jim