acceptable oil use

Curious about what is considered acceptable oil usage (if any) in my 3.4 I recently bought the truck with 115000 miles and racked up 3000 miles since the last change and noticed I'm down a 1/4 quart on oil according to the dipstick. I'm not sure what oil was used on the last change either. Is this "loss" acceptable for these motors and what exactly is the drain interveral? It should be noted that, I didn't perform the last change and I can't say with certainty that it was even filled properly. I may just change it and monitor it myself.

 

Thats a pretty big lost id imagine, I've got 203,450 and i never lose any oil and I usually go 4-6k before changes

 

Until you do it yourself, there is no way to be certain that you are consuming any oil.

At 115K, it seems unlikely that it is burning it past the rings or valves. The 3.4L is pretty amazing motor as long as it is properly maintained.

If it has dinosaur remains, 3K is time to change it out. I only run synthetic and typically change it between 5-6K.

 

You might check the backsides of valve covers and see if it's oily. Does your truck blow smoke when you start it.

 

Might change the pcv. When those go they can contribute to oil consumption. There pretty cheap also.

 

I concur with the others. Mine had 100k miles when I bought it, approaching 140k now, and I see no evidence of consumption between changes.

Also make sure that when you check the oil level, you eliminate variables. Do it on dead level ground every time, or at least that the truck is in the same position/orientation each time; for example, if your driveway has a little slope, like mine did. I would get slightly different reading if my truck was facing up or down my long, very slightly sloped driveway.

 

thanks for the input so far guys. I've made an habit out of checking for smoke on start up after my injectors went out on my Duramax and my Toyota does not smoke at all.

I did notice the passenger's side valve cover is slightly wet on the back of the engine. Other than that everything else looks dry. Not sure how to properly check PCV function, but it does "rattle" when removed.

I'm thinking of just doing an oil change in the next few hundo and monitor it from there. My guts telling me it was a case of "eh close enough" at the hick garage when the previous owner had it changed.

 

Not sure about the 6 cyls but the 2.7 is famous for valve cover gasket leak on back side. Those bolts work themselves to almost hand loose. But once you know......

 

Same on the 6 too, retighten them unless you want to just go ahead and change all the gaskets: valve cover, spark plugs o-ring