so u leave in in the "3" spot on the gear selection indicator with the tow/haul button activated? does leaving it in 4wd in the 1/4 damage ur tranny at all? im used to the "dont go over 55 in 4 high" and "dont go over 20-25 in 4 low"

ya we need to meet up sometime so u can give me some pointers, especially since we are so close, me living right off of gibbs lol

ya im with you, i have 160,xxx something on my truck lol

see my reply to black00chev, but when u mean leave in in third do u mean leave in gear selection 3 with tow/haul on or leave in drive with tow/haul on? correct me if im wrong but doesnt activating the tow button remove the 4th gear and lengthen gears 1-3 for more torque?

 

Tow haul doesn't remove 4th gear but it does move shift points up and changes when the converter locks up. It also increases the fuel supplied to the engine.

I am talking about leaving the gear selector in 3rd. I normally don't use tow haul ever even when towing because my MPG goes to crap.

 

Tow haul does nothing to effect fueling, as for it effects on shift points it depends on how it is tuned.

 

if u leave the gear selector in 3 wont it leave off the line like a dog?

 

i leave in drive with tow haul mode on area47 tunes the shifts better in tow haul. i foot brake 1500rpms and leave at half pedal for about 10 feet then mash it.

 

ya he tuned mine as well. i didnt have the vette servo in it when he tuned it so im not sure what tuning he did when the tranny. ya ill try leaving it in drive with tow on

 

From personal experience I respectfully disagree. Stock 2000 ecsb 4.8, when tow haul was used on multiple occassions the fuel trims, both short and long term, were in the plus 20 range and the truck would get a best of about 12 MPG no matter how easy I was on it. With tow haul off and leaving the trans in third, only shifting into over drive once up to highway speed, I could get 15-16 MPG. Also, the shift points were extended about 10 MPH or so and the converter would not lock below 60 MPH when tow haul was used. So in my particular case, bone stock truck, tow haul did affect fueling and shift points.

 

Do you have tuning software and or know how to tune? It does not have the ability to change fueling, it effects the trans only. As for fuel trims being different that is because you would have been in a different range of the VE table and therefore a different fuel trim cell due to the change in engine load from the trans shifting different. It effects trans function only, shift points, converter lockup speed, shift pressure and shift time.

 

As for trans gear selection, I am not really a sure on a 60 as I never had any issues running mine in drive. On a 80e by running it in 3rd it applies the overrun clutches, I run my 80e in 3rd when beating on it.

 

Well i went to the track today and made about 5 or 6 runs. Best 1/4 time was 15.7 @91 with trans in drive and tow button on