Ok so I am fully aware how to check a transmission fluid level. I check it in the morning after sitting all night and im right in cold marks after firing it up. I drive to work (15 miles) after letting my car warm up for 5-10 mins and check it and im just below the lower hot mark, mind you its a 25 min drive with some highway. I drive downtown and back (about 40-45 miles) and check it when I get back without shutting engine off and im a half inch maybe a notch less over upper hot mark. Any ideas? should I even worry? I check it with engine running in park on level surface and no fluid on the fill tube walls. I got 40k on the rebuild.

2000 Blazer 4.3 205k miles

 

I always check them hot while running, don't ever worry about it cold unless I come out and see a big puddle under the truck.

 

Owners manual seems to suggest hot is the best way to check it. With engine on, shift through the entire gear range, pausing 3 seconds each time you shift. Then check the level.

 

Thats when I check it 99% of the time. So why the half inch over after a longer ditance? anything to worry about? It rund fine and no bubbles on the stick.

 

Dont worry

 

Transmission fluid must be checked with the vehicle on a level surface, the engine at idle, transmission in park or neutral, and the transmission fluid at operating temperature. If ambient temperature is below 40 degrees F, the transmission & the cooler working properly, you're looking at 20+ miles before the transmission fluid has stabilized at operating temperature. If you have an external transmission cooler, it'll take longer. If you bypassed the OEM cooler in the radiator, it'll be even longer still. The hotter the fluid is, the higher it will indicate on the stick.