There is a (looks like) 3/4" hose right above, pointing down on the 3rd member on the front axle. that blows quite a bit of oil. what is this for?? blowby??

 

Yep, that is the crankcase's vent tube. They are vented to the atmosphere on these engines.

 

quite a bit of oil comes out that tube. does that mean alot of blowby? how do you determine if you have alot?

 

with your mods i wouldnt worry about blowby. if you think you have alot because of the layer of oil under your engine, thats normal. look at it as a rust inhibitor.

 

It's normal to have a little wet spot on the differential below the vent tube. But if there's enough oil that it's blowing back and soaking the transmission, that's not normal. I've seen a couple trucks where there's enough oil coming out of the vent tube that it's dripping off the back bumper. That's too much.

 

Hey torquefan , there is enough blowing out that i need to wipe off the trans everytime im under there doing a engine oil change. whats the fix for this?

 

What has worked for me is to extend the tube a few inches from the ground by slipping some larger tubing over the stock tube. No clamps needed if you use the right sized hose.

Paint the pavement not the bottom of the truck.

 

good idea. im going to do that.

Does all this mean my motor is getting tired? i have 290K on it.

 

if you have excessive blowby one culprit could be that you have worn piston rings, which when this happens the piston does not make as tight of a seal on the cylinder walls and allows the compression to leak by and blow the oil out of the crankcase, and therefore out the breather, however like said if you are not blowing oil all over i wouldnt suspect the rings are bad, but it might not hurt to have the compression tested.

 

The first thing to check isn't actually engine related. Check for a leak in the truck's vacuum system. The vacuum pump is powered by the engine and provides vacuum for the cruise control, 4wd actuation and HVAC controls. The vacuum pump is vented to the crankcase, which works good if there are no vacuum leaks. However, if you get a vacuum leak, the pump sucks in air at the leak, and will pressurize the crankcase, which vents out the breather tube, carrying oil vapor with it as it leaves the engine. Clear as mud?

It's nice and easy if this is in fact the culprit, if not, engine wear is the likely cause, and Infidel's advice is a great solution.

 

that last comment was very helpful to myself. My cruisecontrol quit working properly and I started to get more blow by at the same time ...

 

Been dealing with a little puddle and no cruise for several months... just got my head out of my A$$ and checked the vac lines. Found a leak right near the pump! Fixed it, now cruise works and no oil leak!