Now that I've got all the bugs worked out of my Suburban and am using it to tow, I'd like to prevent unnecessary wear on the transmission. I can get a shift kit, which modifies the valve body, or a shift improver, which accomplishes the same line pressure increases to the clutches electronically. Which is better from a functional standpoint since they cost the same? What about using both? I kinda like the fact that with the B&M shift improver you can select between operating modes (hard & soft, like ice cream, LOL.)):h

When I called B&M their recommendation was to go with the body over the electronic, the kit comes with 2 race or tow I selected tow. define tow, how many lbs, cooler is better , I added 25K rated electric fan & cooler & deep pan, I also had HD clutch packs put in as well

TD
Does the B&M kit address the pressure regulator valve train and cross drill for lube? I have found the Transgo shift kit to be the best at fixing poor factory engineering ( dangerous spiked pressure and cooler flow from the converter)
mike

define tow, how many lbs, cooler is better

I won't be towing anything over 7000 lbs, just a 20' fishing boat or a trailered Jeep.

Is the factory tranny cooler insufficient?

I'm just concerned about slippage... if I can avoid that then there will be less heat to dissipate. Doesn't the shift kit, by increasing line pressure, reduce clutch slippage? I don't have any tranny problems now I just want to avoid causing any in the future.

Any opinions on the ATP kit? $50 at Rockauto, but you get what you pay for, I imagine.

I didn't install it myself to know about the regualtor I had it installed same time I had my trans builder install HD clutches, it was drilled as I asked if it could be reverted back to stock & I was told only if I got a new body. For specifics call B&Ms tech line they were pretty helpful, that said after getting the B&M I have heard other trans builders say they like the Transgo over the B&M, but no-one ever clued me in on why.

Factory should be sufficient but pulling heat is never a bad thing, I pull up to 18K on occasion with mine ergo I wanted max cooling 3 coolers, radiator tanks/grille mount factory cooler & Deraile under bed one with thermostat controlled fan. (remember though a cooler trans also helps engine heat as radiator has less trans cooling/heat xfer to deal with)

The trans kit does apply firmer pressure & how I would go. With a 97 what you are up against is computer controlled torque converter lock up which locks & unlocks constantly to keep from overloading hollow input shaft IIRC, so we will always have more than desired slippage & extra heat, earlier model 4L trans could be lied to and voltage forced to keep the TCC locked, not so with a pulse width modulated lockup as in 96+ OBDII, most effective lockup with these is reflash that changes the PWM TCC parameters/curve.

The trans kit does apply firmer pressure & how I would go. With a 97 what you are up against is computer controlled torque converter lock up which locks & unlocks constantly to keep from overloading hollow input shaft IIRC, so we will always have more than desired slippage & extra heat, earlier model 4L trans could be lied to and voltage forced to keep the TCC locked, not so with a pulse width modulated lockup as in 96+ OBDII, most effective lockup with these is reflash that changes the PWM TCC parameters/curve.

Hmm, so wiring a manual TCC lockup switch isn't possible with the later tranny? And even if it were possible it isn't such a good idea then, I take it.

That is about the size of it, puter controls lock up, several companies offer a controller, but IIRC they can set codes and put tyrans into limp mode, and has to be manually disengaged below 35mph doesnt self engage/disengage