PossumTruck
Registered User
(I have no tach, so MPH is really my gauge) What exactly are the shift points for a 6.9L with a t-19? Specifically, I'm working through losing a power bad in the 3-4 shift. At one point, I was doing research and was told about 35 mph was the high end for 3rd gear. I knew that wasn't right because I could run it to 45 when I wanted (and the engine sounded loud), but it drove better that way. Rear axle is a Sterling with a 3.55.
My issue has been that the 3-4 is basically that I lose power as soon as I shift to 4 - and in a way that seemed odd/pathetic.
I could strain on the road to keep 55 on a steep hill, unloaded. Unburnt fuel cloud and all.
Today I took 3rd gear over 50 mph a few times, sure made the 3-4 better, but my reading/research has told me that is way too fast.
Any insights? Truck is a Cab & chassis, not sure if that has an effect on the ratios or if my research was bunk.
My issue has been that the 3-4 is basically that I lose power as soon as I shift to 4 - and in a way that seemed odd/pathetic.
I could strain on the road to keep 55 on a steep hill, unloaded. Unburnt fuel cloud and all.
Today I took 3rd gear over 50 mph a few times, sure made the 3-4 better, but my reading/research has told me that is way too fast.
Any insights? Truck is a Cab & chassis, not sure if that has an effect on the ratios or if my research was bunk.
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