ive got a 1988 chevy conversion van with a 350 that suddenly started losing oil i took it to new mexico the trip out went fine till i got to amarillo then in the 285 miles back to my house it used 6 qts of oil what could cause this to happen its not leaking or smoking i have thought the pcv valve but wanted some more insight before i tackle this

 

It has to be burning it if it was leaking there would be oil on the rear bumper (sever leak) and oil under it every time you parked it. It could be sucking it thought the pvc valve or blowing it out the fresh air intake side of the pcv system. It is also possible that it is burning due to bad valve seals or rings. Se the article below it could explain why you do not see smoke.

https://www.carchex.com/goss/article...rter-confusion

 

thanks for the advice i dont think the rings or valves are the culprit simply because wouldnt they happen over time this was a kinda sudden thing

 

Hi rdnkrfnk,

Welcome to the Chevy Forums.

There's a couple possibilities come to mind. Were you using a dipstick to check the oil, or waiting for the warning light? Because sometimes the senders for the warning lights hang up and don't register low oil right away. This might explain how you averaged a certain amount of oil loss without knowing it until the last leg of the trip..

Also, a PCV valve could stick open, which could increase your oil consumption. The telltale for bad rings is blue smoke out of the exhaust. For the amount of oil you used in such a short distance, it would be a fair amount of smoke.

 

i checked the oil before i left out i drove from tucumcari new mexico to amarillo takes round 2 hrs then from amarillo to home takes round another 4 hrs the light came on between amarillo n home