Not sure if this is the right section..but Ive got a really nice 1995 K2500 Silverado, runs like a top, 128K original miles, meticulously maintained engien and trans, Ive noticed some traits im unsure of.

When crusing, I feel it hit 2nd, 3rd, 4th, and Im assuming its locking up the convertor in 4th..as the tach barely responds when I punch it down...When p edal some..the rpms goes from like..1800 (@55mph) to 1000...and if I touch the brake at all, it drops to 600......Is this normal?

If Im towing a light load, or even not towing...and I come to a hill, or incline...again, 55mph turning 1800 rpms....the truck starts to lose speed..I give it some pedal and it will stop losing speed but it wont accelerate unless I take the pedal prety much to the floor and force kickdown...at which time it will rapidly accelerate..until I back off the pedal at all..then its back to 4th/lockup instantly...

What can cause this? Ive got no dummy lights lit up, and all are working...