TCC Lockup (Can't Figure This Out)

[flipmo]

Guys, I'm trying to figure something out that kind of has me stumped at the moment. Well, long story short I'm trying to rationalize what's actually going on with my Tranny and TCC Lockup.

Two of my previous GNs had a TCC switch installed inside the car that I could lock up manually with a flip of the switch. One of the convertors was a TCS Race 9.5 L/U Convertor and the other was a Vigilante 9.5 L/U Convertor. With both of these convertors I could lock them up on the street and go cruising with absolutely no problem and simply haul ass through all the gears with no problem. This includes regular driving, street and drag-racing both of those cars.

Well, with the current car that I have, the tranny is brand new and the convertor is a PI 9-11 3800 RPM Convertor.

Issue: When I lock this particular convertor up on the street and try to go through the gears it boggs the car down really hard. It's like there is a big strain on the engine and tranny that's keeping it from wanting to move (kind of slugging along). When I lock it while parked and initially pull off I can feel the extra torque through 1st gear intially and then for some reason it quick shifts into 2nd gear and boggs really bad. It never shifts into 3rd gear with convertor locked at slower speeds and barely wants to go while mid-1st and all of 2nd gear (bogg, bogg, bogg). When I unlock this convertor it then again hauls ass immediately. As long as I leave it unlocked the car flys with absolutely no problem.

But: When I lock this convertor manually at, say around 3rd gear going about 85 mph or faster, the car hauls major ass. It feels like someone gave it a 100 shot of nitrous and I can feel the car just bites and go! At 85 mph or faster there is absolutely no bogging or hesitation whatsoever and the rpms and mph both increase with no problems, which has me somewhat stumped because I can't figure out what is going on with the car at the slower speeds with convertor locked that creates this terrible bogging which makes the car hate to have convertor lockedup up in 1st or 2nd gear.

Question: Is there something special about this particular convertor that I'm doing wrong? Could it be that this convertor was simply designed to work this way? Am I basically locking the convertor when it shouldn't be locked because it doesn't make sense. If I could lock the convertors on my last two GNs anytime I wanted and not have any problems, why is this one not allowing me to do so in 1st and 2nd gear and only likes to be locked in 3rd gear or higher at or around 85 mph or faster. Tell me if you think everything is O.K. or whether or not I may have a problem.

Please Square Me Away and Thanks

flip

 

[Turbo6Tech84]

My first guess would be a bad TCC solenoid. I've heard of cars bogging out when the TCC goes bad. Yet again this is just a guess maybe someone alittle more knowledgable has a better answer

 

[flipmo]

My first guess would be a bad TCC solenoid. I've heard of cars bogging out when the TCC goes bad. Yet again this is just a guess maybe someone alittle more knowledgable has a better answer

Thanks but it just doesn't make sense. If the TCC will lock in 3rd gear at high rpms and high mph O.K., I would think that it should be O.K. through 1st and 2nd gear as well.

Maybe there's something I'm missing here. That's why I said earlier two previous convertors I had were O.K. throughout the gears. It is just this one that doesn't like the lower gears and boggs like crazy when switch is on.

I think I'll just leave the TCC unlocked until someone can explain to me what is going on. Plus, I prefer consistency over anything else as there currently is no way I can consistently lock the convertor each and everytime at the same point in 3rd gear at 85 mph or better. I'd screw that up everytime.

Thanks Again

flip

 

[GNVYUS 1]

The answers in front of you, did the factory engineers design the lock up to lock in 1st, or 2nd let alone while you are pulling away after putting it in gear??
Notice how many rpms the lock up eats up while in 4th doing 50mph, that amount of reduction is almost like another gear has been shifted into. You are doing that in 1st and 2nd and for a while now??

It is a good thing that you are bogging while in 1st and 2nd, that means you finally found a converter with a strong lockup clutch that you can not drive through.

Personally, I would get a chip that has the lock up feature only in 4th at 45mph, and at WOT/80mph in 3rd. I would only use this chip at the track or on the dyno, there is no need to continuously lock up the clutch like you have been.

 

[HighPSI]

The previous owner used to leave it unlocked except when he was on the freeway.

 

[flipmo]

The answers in front of you, did the factory engineers design the lock up to lock in 1st, or 2nd let alone while you are pulling away after putting it in gear??
Notice how many rpms the lock up eats up while in 4th doing 50mph, that amount of reduction is almost like another gear has been shifted into. You are doing that in 1st and 2nd and for a while now??

It is a good thing that you are bogging while in 1st and 2nd, that means you finally found a converter with a strong lockup clutch that you can not drive through.

Personally, I would get a chip that has the lock up feature only in 4th at 45mph, and at WOT/80mph in 3rd. I would only use this chip at the track or on the dyno, there is no need to continuously lock up the clutch like you have been.

Dr. Booster, thanks for the info, but I travel all across the various Buick boards out there and recently (yesterday) I can't tell you how many times I read that you should always have your convertor locked while driving on the street. Then again, an equal number of people say they don't lock theirs on the street and only lock it at the track. So, one thing I'm kind of figuring out is, "That like you said, it must be the way the tranny and converter was designed and built (i.e. to function a certain way)". The thing is I just don't know how this convertor was designed to function.

Most say locking it on the street will prevent the massive heat buildup if you have it unlocked. That's the way I ran my other two cars anyway. But this GN hates the early lockup. Well, I'm running the F.A.S.T. and not a chip, and I'm quite sure the tranny adjustments in there has nothing to do with a convertor lockup. However, I could be wrong.

Thanks

flip

 

[flipmo]

The previous owner used to leave it unlocked except when he was on the freeway.

Ohhhhhhhh, O.K. Cal, I should have called you anyway as I'm sure you would have known something about this car. I was just so mind boggled I didn't think to do that.

Any particular reason why he did it that way? Was it just designed to function at high mph/rpms? So to make sure I don't screw it up, I think I'll drive it the same way.

Anymore details you can provide about this?

Thanks

flip

 

[brian]

Most say locking it on the street will prevent the massive heat buildup if you have it unlocked. That's the way I ran my other two cars anyway. But this GN hates the early lockup. Well, I'm running the F.A.S.T. and not a chip, and I'm quite sure the tranny adjustments in there has nothing to do with a convertor lockup. However, I could be wrong.

They are talking about having it lock up on its own in OD. Not through all the gears.
I guess it would lug during "normal" street driving.:smile:

Brian

 

[HighPSI]

Ohhhhhhhh, O.K. Cal, I should have called you anyway as I'm sure you would have known something about this car. I was just so mind boggled I didn't think to do that.

Any particular reason why he did it that way? Was it just designed to function at high mph/rpms? So to make sure I don't screw it up, I think I'll drive it the same way.

Anymore details you can provide about this?

Thanks

flip

He used to have a non-l/u in the car. It was hurting his freeway mileage so I put a l/u convertor in. He basically used the convertor the same way. He just locked it up when he got into 4th gear on the freeway. If you lock it in the lower gears, it may lug the engine down too far.

 

[GNVYUS 1]

I think you are misinterpreting what you are reading about the lock up, when people say they are using the lock up on the street, they are generally just letting the computer do it like it was designed to do for fuel economy and tranny heat reduction/engine wear etc, in 4th around 45mph.

Don't lock it in anything other than 4th on the street around 45mph, then lock in 3rd around 80mph for all out WOT mph at the track. Personally, I would take the clip out of the ALDL and only install it at the track, let the tranny lock it up for you in 4th. I also wouldn't lock it at WOT on the street in 3rd due to clutch wear, if you can't win on the street by 3rd then just add more goodies to the list.

 

[flipmo]

Guys, I got it now. I just simply needed the concept explained to me in a little more detail. I see that the convertor I currently have was simply designed to be used in a certain way (3rd or 4th gear at higher mph or WOT). Damn, I hate to say it but I always thought all convertors kind of worked the same way, then again, I guess I was just so use to the way my last two tranny convertors were set up (i.e. thump the TCC switch in 1st and try to beat the other guy!!!).

Live and Learn:biggrin: :biggrin: :biggrin:

Thanks Again Guys

flip

 

[flipmo]

He used to have a non-l/u in the car. It was hurting his freeway mileage so I put a l/u convertor in. He basically used the convertor the same way. He just locked it up when he got into 4th gear on the freeway. If you lock it in the lower gears, it may lug the engine down too far.

Cal, I sent you a PM.

flip