Looking for some advice.....I have an 08 F250, 6.4 liter with roughly 130,000 km on it. Truck is tuned and so is transmission with H&S tunning, great tunning by the way. Question I have is the transmission tuning comes with a few different shift schedules, lower and higher torque converter locks and shift and shift points etc. The shift schedule I like and also seems to get the best mileage has the lowest shift points, with 4th locking the torque converter hmmm i think around the 30 mph range( have to double check to be sure of exact speed). Question I have is.....when slowing down and coming to a stop, the torque converter stays locked in 4th gear a bit below the 30 mph range, producing a slight vibration noise, nothing i can feel in the truck or anything like that. Rumour has it this is torque converter chatter that i am hearing.....Is this bad for the truck or more so just a noise and nothing really to worry about? Ive also asked this on their forums a few weeks back...guess just looking for more insight/opinions from the guys here as well. :-)....Any advice or insight much appreciated.

 

Well, after some searching, I figure this unanswered post might be a good one to chime in on and "subscribe" to, as I have some related questions.

About a month ago, I did a 400mi. round trip to VIR and back, down Va. Rt. 58, it's quite "hilly" and 60mph max...the "Lie-O-Meter" as you guys seem to enjoy calling it rewarded me with a "score" of 12.4MPG. Last week, I drove about 1000mi. round trip to Road Atlanta and back, so there was 2hrs on 58 and 6hrs on I-85, averaging 70mph with a lot of 78-80mph when the signs said 70.

The "Lie-O-Meter" penalized me with a low score of 9.8MPG - I was shocked.

I am DPF delete with an H&S Mini-Maxx set on "Mild" for towing...the torque converter is set to lock up immediately in the higher gears. I wonder, would I get better mileage and less downshifts if I selected a non-lockup mode or didn't allow lockup until higher RPMs or is this the best it's going to get?

I was mildly satisfied with the 12.4MPG but that was my first tow and I towed very early in the AM, little traffic and the 28'/10,000lb trailer (loaded) seemed to push the truck up hills and such...and I probably wasn't as heavy on the throttle...so I may have answered my own questions with regards to WHY I yielded considerably less MPG on the Atlanta trip.

SO, while I'm not getting "torque converter chatter" like sxrfun, I'd like some advice on changing my software settings to allow lockup at higher RPMs/load, etc. -vs.- letting this thing lockup immediately upon switching gears.