I will ask again. How is the new 18-037-04 reflash working with the trucks with the automatic trans.? I had the 18-007-04 reflash in Feb. . It included a change that allows the auto trans. converter to lock when a manual 2nd gear down shift is selected. This is great in town. I did not like the fact that the reflash gave my transmission a higher r.p.m. unlock, when slowing down in 3rd. Has the new 18-037-04 reflash effected the converter lockup and unlock in the automatic trucks? Again the 18-007-04 reflash unlocks the converter about 200 r.p.m.'s higher when slowing down in 3rd tow/haul. The unlock now is about 51 m.p.h. from the stock 47 m.p.h. with the original software that came with the truck. This higher unlock r.p.m. is not good when towing in the hills.

 

I'm too dumb to answer any questions about lock up or anything of that nature, but I will tell you that my 48re is now much smoother. It doesn't hunt for gears when getting back on the gas ( I mean fuel) to climb a hill after I have just come down one. The most impressive thing to me is that now it shifts normally into OD. Before it was somewhat violent when shifting. I don't know much if anything about transmissions, but I was very unimpressed with the tranny before this reflash, I'm still unimpressed but it feels more normal now.

 

Has anyone with a automatic transmission had the 18-037-04 reflash? It is easy to tell when the converter unlocks as your engine r.p.m. drops and you have lost most of your engine braking. When it's locked up, its more like a stick shift. Thats why in town I put the truck in 2nd tow/haul and use very little of my brakes when coming up to a stop sign. I have the 3.73 axle and the unlock was 47m.p.h. in (D) tow/haul when slowing down.

 

It does NOT affect torque converter lockup... Still only locks up in overdrive unless you have the tow-haul selected or in 2nd gear.

Had it last week. All I can see is the overhead shows more mpg than hand calcs.

 

I'll 2nd that it behaves the same as before.

 

I agree also, seems to act just like before the TSB. That is except the overhead computer mpg. I just hope it is correct now, but I wont hold my breath.

 

Had the 18-037-04 reflash done. It controls the lockup on the transmission the same as the earlier 18-007-04 reflash I had done. If you have a early 04.5 automatic transmission truck, both reflashes will cause the unlocking of the converter sooner when slowing down in tow/haul (D). The original software that the truck came with unlocked at 47 mph when slowing down a hill. Now it unlocks at 51 mph. Just for your information.