bumsquad69

I have a 2007 chevrolet silverado vortec max 6.0l with about 115,000 miles on it, the other day while driving going about 55 mph it felt like i lost all power and my rpm's went up to about 5,000 i let go of the gas and it felt as if i grabbed gear again and acceleration picked up again, the next day while casually driving it did it again this time it completely slips in third and fourth gear until i rev up the engine to about 4500 rpm's then it grabs a little while in drive, i have to keep it in second gear to keep it moving cause third and fourth gear does not grab and i just rev the engine as if it were in neutral, it had always shifted hard from first to second gear but idk if that is related to my current problem, also while in drive once it passes second it seems to have a sort of a little bang oncein awhile, i have no codes, has anyone else ever had this problem? Thanks for your time.

burhead1

Do you use a aftermarket oil air filter (like K&N)? these can contaminate the mass ir flow meter and cause shift problems. You say you have no codes, did you scan the TCM? or do you just not have a engine light on? It sound like you accelerate and it seems to go into neutral if so you may have a bad sprag clutch, it is a one way clutch which is supposed to hold the sun gear. If it goes it will be as if there is no drive(neutral). If it were a electrical or solenoid problem in most cases it will not shift.

bumsquad69

I do have an airraid air filter and i did clean and re-oil it right before the problems started, and if the sprag assembly were going out would'nt that still affect first and second gear as it is strong and normal in those gears and in third and fourth gear it seems to be in neutral as i accelerate until it hits about 4500 rpm then it seems to grab a little. Ihave no engine light on but i have not scanned it as i am planning on doing that tomorrow morning.

burhead1

I would take some brake cleaner or mass airflow sensor cleaner and clean the mass air flow meter first. yes if the sprag were going it can just affect the 3-4 as there is two planetary sets in that trans.

Georgiey22

Did this solve your issue?