Jimmy04

Sorry if this is not the forum to ask, I'm new.

​​​​04 Silverado 2500hd 4l80e lq4
Engine and tranny slowly overheats when idling and in stop and go traffic. Ones the engine gets to 210 my transmission starts to overheat, and both keep climbing. It has gone into limp mode once
I've replaced-
Water pump
Fan clutch
Thermostat
Resivor cap
Installed 3 row rad
Installed 40k tranny cooler
New rebuilt transmission and converter less then 1000 miles.

Has a code for evap leak and evap plunger

I'm at a loss.
Thanks

wretched73

iTrader: (1)

Any codes? Are you building pressure in the cooling system? Cracked Head? Blown Headgasket?

strutaeng

Yeah. What is the history with truck also?

You've just bought it? Or you owned for a while and it ran good before?

Has it ever overheated before? You can rent one of those coolant tests to see if you have combustion gases. Or the coolant pressure tester. The local parts stores should rent both of those.

Jimmy04

dad bought it new i bought it off him at 180000 miles and about 20000 miles later it started overheating. He used it for road construction and as a farm truck after he retired. i use it as a work truck hauling trailers and material. so yha its had a hard life.

Jimmy04

no symptoms of a blown gasket or cracked head. it must be small if it that is a problem.

wretched73

iTrader: (1)

Air pocket in the cooling system?

Is the fan damaged? Still have the stock fan shroud?

Not much to go on here.