Torque converter lockup

[colfaxent]

Hey can anyone with a stock truck with no tuner and 3:73 gears tell me what speed /mph your converter locks up at.?

[roor44]

would also like to know

[Jarrod B]

depends. speeding up. right after 40mph with a moderate acceleration. speeding up fast, easily after 50mph. but then when slowing down it can hold it till 37mph.

[08stroker250]

50 mph seems to be the speed that it locks up at stock ON A 6.4

[rodo]

48-50 mph for me.

[colfaxent]

Thanks for ther feedback guys, what do you feel is a good speed to lock on Tuned trucks, My Black Maxx locks at 60=61 and seems a bit late to me . Hard to get up to 60 in normal DD driving in my area . What does the Spartan 275 lok at? JIM

[08stroker250]

Originally Posted by colfaxent

Thanks for ther feedback guys, what do you feel is a good speed to lock on Tuned trucks, My Black Maxx locks at 60=61 and seems a bit late to me . Hard to get up to 60 in normal DD driving in my area . What does the Spartan 275 lok at? JIM

The 275 tune will lock up at 45 mph normal driving. Not real sure what it will do at WOT...maybe earlier. I know my 310 tune would lock up in 3rd gear at WOT from a 4x4 boosted launch at the track. Not sure about the mph. Normaal driving with the Spartan TCM I have been locked up at 42-45 mph with the 310. Have you tried the race shifting trans files from H&S? They will improve it gretaly from what I understand.

[colfaxent]

Thanks , Yea I tried the race file also, I like it but my wife drives it DD and it shifts a little abrupt for her. Lock up came down to 55=56 but you are right it does shift nice. Firm file is actually very good tho, just feel i need earlier lock up. Think I will look for a change about 48-50. Should help MPG also. IMO

[08stroker250]

Yea, it will help your MPG for sure!

[Tarheel_6.4L]

mine locks up right at 50-51mph