Engine/Transmission (1994 - 1998) Auto Trans and Triple Disc Converters

[Cooker]

With 300HP and a "low stall" stator you would be lucky if you truck will get out of its own way during a flat footed "no boost" take off from a light, or pulling a load.

Justin, are you referring to a truck at elevation correct?



I spent some time today running around town with a skidsteer in tow, at less than 300HP via my valet switch and with my low stall stator, and I would certainly have to disagree with that statement. Of course here in Michigan we do not hardly qualify for above sea level elevation and 7500lbs is not really "towing" because the I can't hardly tell it's back there

 

[jimk]

Just because a triple disc converter works on the drag strip does not mean that it is needed in a towing or street truck. Can it be used there? Yes of course, but the debate is pretty much just a good excuse for bragging and chest-beating. Sir do you have to unlock a single to protect it at full throttle. I dont intend on unlocking the converter unless I have a reason. I dont have a thing against a tripple disc converter, or spending the money to get one if it is stronger. My transmission is stock so it would be a great thing to have a 89h and tripple disc, billet cover, regards Jimk

 

[Lsfarm]

Unlocking the TC

There is an 'urban legend' or maybe a historic precedent about having to unlock a single disc TC to 'protect' it under full throttle. Years ago there were 'TC saver' products sold to unlock the TC under full throttle. These are not needed anymore with the advances in VB technology. The TC doesn't need to be protected anymore.

The only reason DTT has the unlock feature built into the Smart Controler is to give the trucks with tall tires and 3. 55 gears a pseudo passing gear when full or part throttle is applied. This feature is adjustable from the cab. About 2-300 rpm increase is seen with the TC unlocking.



So no, there is no reason to unlock a single TC to protect it in any way. In fact unless the truck has the Smart Controller box installed [which is an option], the TC will stay locked and be controlled by the PCM anyway.



Greg L.

 

[wilddiesel]

Justin, are you referring to a truck at elevation correct?



I spent some time today running around town with a skidsteer in tow, at less than 300HP via my valet switch and with my low stall stator, and I would certainly have to disagree with that statement. Of course here in Michigan we do not hardly qualify for above sea level elevation and 7500lbs is not really "towing" because the I can't hardly tell it's back there

Along time ago I had talked about this same issue of having to tight of a TC at higher elevation. When you live at 4500 to 5000' and have to drive a truck around with a low stall TC and high power and emission police running around everywhere be prepared for a ticket due to excessive smoke. Take off on a 6% grade with a trailer in tow and a low stall convertor trying to keep up with traffic and poof instant ticket. Now put a higher stall TC in and do the same thing considerably less smoke and no ticket. This emission stuff is getting very serious here in SLC. One other thing I have seen with non billeted TC lids are broken face lugs although not alot I have seen them. This information on this thread has been informative to alot of people, once again it is up to the individual as to what he wants- shop hard. All of these TC and transmission have been out a long time now there are no more secrets to TC they have all been cut open to see what the competitor uses. Some prefer to upgrade some dont. I think the big story here is that you are happy with whatever you purchased. There are pros and cons to everything just dont fall for the smoke and mirror treatment.

 

[DavidTD]

Question.



I travel everyday in this wonderful Atlanta traffic. There is a 8 mile span that takes about 1 hour to travel. With the different converters I have tried, the tighter they are, 1) the harder pressure I have to apply to the brakes to hold it at a stop, 2) the temps rise quickly while this is happening. Is this normal?



This one is mainly for the 12v's. Most of these trucks shift very quickly into 3rd gear. An example would be a slow roll on with very little throttle and by 20 mph I have seen trucks in 3rd gear. With a tight stall, doesn't this make applying throttle more of a lag situation since the motor cannot rev easily? I understand, more throttle, it will downshift, but in every case I have experienced this results in black smoke until the downshift and resulting rpm and boost.



Same situation with slowing to make a turn. With a 12v, especially one that runs large injectors, the truck will not downshift below 3rd until you are nearly stopped. Same result as above. Is this common?



And BTW that was an excellent post Greg. I ask this question because I have a friend with a 12v that pulls a 5th wheel with a tighter stall. He complains about the smoke constantly. As a matter of fact he has removed injectors, and about 100hp to get rid of it.



Thanks,

 

[bmoeller]

I travel everyday in this wonderful Atlanta traffic. There is a 8 mile span that takes about 1 hour to travel. With the different converters I have tried, the tighter they are, 1) the harder pressure I have to apply to the brakes to hold it at a stop, 2) the temps rise quickly while this is happening. Is this normal?

It is normal. When you are stopped, you should have the truck in neutral. The temps go up because you are fighting the T/C. It wants to move the truck, when you don't want it to.

Most of these trucks shift very quickly into 3rd gear. An example would be a slow roll on with very little throttle and by 20 mph I have seen trucks in 3rd gear. With a tight stall, doesn't this make applying throttle more of a lag situation since the motor cannot rev easily?

May need to adjust the throttle valve cable, to prevent the early shifts, if that is the case. Being in 3rd gear, at light throttle (as driving in town) and going about 20 doesn't sound unusual.

With a 12v, especially one that runs large injectors, the truck will not downshift below 3rd until you are nearly stopped. Same result as above. Is this common?

I can feel mine downshift. The injectors wouldn't have an effect on the shifting, just the amount of smoke if the engine is being lugged. The TV adjustment may help this also.

 

[justinp20012500]

Along time ago I had talked about this same issue of having to tight of a TC at higher elevation. When you live at 4500 to 5000' and have to drive a truck around with a low stall TC and high power and emission police running around everywhere be prepared for a ticket due to excessive smoke. Take off on a 6% grade with a trailer in tow and a low stall convertor trying to keep up with traffic and poof instant ticket. Now put a higher stall TC in and do the same thing considerably less smoke and no ticket. This emission stuff is getting very serious here in SLC. This information on this thread has been informative to alot of people, once again it is up to the individual as to what he wants- shop hard. All of these TC and transmission have been out a long time now there are no more secrets to TC they have all been cut open to see what the competitor uses. Some prefer to upgrade some dont. I think the big story here is that you are happy with whatever you purchased. There are pros and cons to everything just dont fall for the smoke and mirror treatment.

Hey Ken, hows it going??



I never did get around to calling you after the stud/fire ring install. I have pulled a trailer sustaining 50 psi for about 5 miles and never had any problems. (except the wife complaing that the singing of the turbos was too loud ) I have another buddy that will be bringing a head to you sometime next week. He is going to want studs too.



As for the above post, I have to completely agree. I have a couple of "ozone depletion" tickets myself. :-laf

Justin, are you referring to a truck at elevation correct?

Yes.



I ran a 89% stator in an old single disk/billet cover TC at a low 345 RWHP and smoke with a load behind the truck was challenging to hide. 4500' in elev is pretty unforgiving. Especially backing a trailer up a steep incline like my driveway. It would smoke and smoke then the turbo would lite and blow the rear tires up in more smoke.



BUT on the race track I loved it!! I could blow as much smoke as I wanted when I was stagging at the tree.



Now I have a set of turbos that have almost no lag, and a lot more HP.



I built a multi disk with that same 89% stator and now it works much better.



At 350 RWHP that "mexico stator" works great. It has a lower stall then the stock one, but still allows the motor to build a little RPM's to get the turbo up on boost.



I even ran the "mexico stator" with 500 HP. Yes it worked, but that amount of HP would push through its stall.





Justin

 

[Lsfarm]

'Stack shifting'

Hi David, if your 12v trans is shifitng up that early, the VB needs some adjustments or tuning. As mentioned above it may be a simple as adjusting the TV cable to have at most 1/16" free play with full throttle.



But often the VB needs different springs for the shift timing. Your trans guy should be able to do this for you.



On my 98 12v it took several tries to get it to shift to my liking. The later trucks have much better shift timing built in from the factory.



Hope this helps, Greg L

 

[wilddiesel]

You got my # brother buzz me up.

 

[JKouzez]

So answer me this i just had my DTT installed this weekend i got the billet input with hub and billet drum with 6 clutch packs is it or is it not okay to use a L/U switch when racing.

 

[I-6DZL]

It's probably best to call your installer/rebuilder, or even call Bill K himself.

That way you have a definate answer. And should feel confident with it.



Curtis

 

[DavidTD]

Hi David, if your 12v trans is shifitng up that early, the VB needs some adjustments or tuning. As mentioned above it may be a simple as adjusting the TV cable to have at most 1/16" free play with full throttle.



But often the VB needs different springs for the shift timing. Your trans guy should be able to do this for you.



On my 98 12v it took several tries to get it to shift to my liking. The later trucks have much better shift timing built in from the factory.



Hope this helps, Greg L

Thanks Greg. You are correct, with my Sun Coast Valve body the shifting has never been better, but this is a real common issue with 12v's especially. I recently changed injectors testing some for Jeff. The response is wicked with little throttle so it is just a given the shifts will be quick with such little throttle input.