Transmissions

Fireman · January 23, 2001

Just had occasion to drive a friends 99 1500 w/tow/haul mode. Does anyone know if GM is working on or maybe already has available a retro-fit kit for like my 98 GMC 1500? Has anyone have experience with an aftermarket product that would produce the same result? I tow a 5th wheel and I can feel the difference between the model years. JC

Shaners · January 23, 2001

B&M makes a product called The "electronic Shift Controller". It gives you 3 settings (stock,firm and hard).

It seems to not only control the firmness of the shift but it may raise the shift points a little too. I installed it on my '97 LD F250 4x4 because I thought the tranny was mushy especially when towing. It worked great and is simple to install. You just splice it into the wiring harness and mount the rocker switch under the dash. Price is cheap compared to the benefits!!! I think I paid ? plus shipping from carparts.com or wrenchead.com.

JohnGMC · January 23, 2001

The B&M kit firms shifts only,the GM tow/haul raises shift points and firms them up.So if you install the B7M you will still need to hold it down manually in drive,but thats not a big deal.

Fireman · January 25, 2001

Thank you both for the above info. Question. I checked out this item at www.summitracing.com/ I see it has a 3 position switch. Is the "off" position really off? In other words, when it is off, does the truck shift as it did from the factory? Thanks. JC

JohnGMC · January 31, 2001

Yes,when it is off,its off.The 99 also has less torque /HPat low RPM than your 98,and needs to kept wound higher to give the same performance,since it is down on displacement,it needs more Rpm's to do the same work-thus the tow/haul mode.