I programmed my truck with the Hypertech PPIII on the 87 Power Tuning about 2 weeks ago. I actually think I could tell a different in performance because today I put it back to stock to see if the problem I am having was due to the hypertech or not, and it is not. Also, I am very impressed with the mileage results. The tank before the hypertech was around 11.5 mpg, then the first tank with the hypertech was 13.5 mpg, and my latest was 14.0 mpg. Pretty exciting stuff. No change in driving pattern as far as I could tell. So far so good, except that it makes my truck ping a little more usual. Definitely better than that Jet chip that was in my PCM. Oh yeah, and it DID calibrate my speedometer with my 285's. I set it to 32.75" I believe, as it goes in .25" increments.

 

I put mine on the 93 setting, and there is definentally a power increase... I dont know if its worth the price but its their...

I run regular gas I might add, never had a ping from it. When I first set it to premium I thought I herd something, but never herd it again so I dont think it was pre detonation.

 

Yeah I want to try it sometime on 93 before gas shoots up to $18 a gallon just to see how it performs.

 

Did the Hypertech prevent the torque convertor from locking in third gear?

 

Nope, same old lockup in 3rd.

 

The TC locking up in third really bugged me[sm=icon_flaming.gif]shortly after buying my truck and realizing it was happening. There is actually a customer complaint TSB to have that function removed from the factory program. I don't have any affiliation with Superchips and actually had a bad experience with two of their sales people butthe Superchips program eliminates that third gear TC lockup. Wow what a relief! Even with the 87 octane setting the truck really comes alive when I push on the gas at 35-45mph since the TC isn't locked. And the TC won't lockup til around 48-49mph so incity traffic the TC isn't locking and unlocking.

 

What is the purpose of it locking anyways?

 

are you guys talking about the TC locking with O/D off...cause it shouldn't ever lock in 3rd unless O/D has been shut off according to my '98 factory service manual as well as my own experience. Just wanted to clarify.

 

Mine locks up without turning OD off.

 

According to the FSM:

The torque converter clutch engages in fourth gear, and in third gear under various conditions, such as when the O/Dswitch is OFF, when the vehicle is cruising on a level surface after the vehicle has warmed up.

The fact that the description mentions (plural) "various conditions" and then only gives one example leads me to believe that there are other times when the TCC will engage in 3rd gear.

Also ... are you absolutely CERTAIN that you're feeling the TCC engage and not just feeling the shift to OD and getting the two mixed up? On my truck ... they happen with a second or two of each other and the sentations and results are the same ... a substantial drop in engine RPM.