LBZ: info
- Thread starter ChadS
- Start date
For a fresh start you should (at the very least) change engine oil & filter (no Fram!), the trans spin on, both differentials.
Engine 15W40 - Rotella or Mobil Delvac or Chevron Delo are most common
Same brand names if you go 5W40 Synthetic.
Differentials 75W90 Synthetic - GM Grape Juice, M1 Synthetic, or Amsoil Severe Gear are common. 4 qts rear and 2 front
Use only an Allison brand spin on filter. Check the vendors section.
Congrats! :thumb:You'll be real glad you did this.
And you could consider a PCV reroute if you want to lose the black oily buildup on the CAC tube.
Engine 15W40 - Rotella or Mobil Delvac or Chevron Delo are most common
Same brand names if you go 5W40 Synthetic.
Differentials 75W90 Synthetic - GM Grape Juice, M1 Synthetic, or Amsoil Severe Gear are common. 4 qts rear and 2 front
Use only an Allison brand spin on filter. Check the vendors section.
Congrats! :thumb:You'll be real glad you did this.
And you could consider a PCV reroute if you want to lose the black oily buildup on the CAC tube.
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All basic stuff Chad. Might need a couple of filter tools you don't already have for the Allison and fuel filter.
That is the hot side CAC tube (Charge Air Cooler). What causes the oil is mainly from the PCV system (Positive Crankcase Ventilation). If you look under the resonator box (the plastic box on the top center of the engine that says 6.6L), you will see a plastic tube that runs from valve cover to valve cover and Tees into the turbo inlet mouthpiece. This draws the combustion vapor out of the crankcase that leaks past the rings and helps ring seal. The drawback to this system is it also gets some oil vapor from the valve covers. This can collect in the turbo and seep past the boots on the CAC tubes creating the dirty, oily residue you see on your truck. The fix for that is either do a PCV reroute like was mentioned earlier or clean it from time to time. I hope that answers your question.
Thanks much for the expaination. Now i have a better understanding To whats going on whats causing the oily residue..Im not well versed enough to do a pcv re route so i guess ill just keep cleaning it.
thanks again.
thanks again.
I know this is illegal but i had a buddy run off road diesel in his two trucks....He blew both motors eventually. Not sure if it was because of the off road fuel or his lack of oil changes..lol. Id have to believe trucks now a days arent set up to run off road fuel...His reasoning "its cheaper" when in reality it cost him two motors..
Off road fuel is the same as on road just with red dye.
Ok...wanst sure what the difference was...
My other question is im giong to be putting new gear lube in my differenctials. I was told to use 75-90..I have two quarts of 80-90 that I could use up on the front diff. Would that oil weight be a problem?
You HAVE to use Synthetic and I wouldn't recommend anything other than 75W90. It's a few $ extra. Why take a risk?
So I notice my brakes on my silverado are real spungy compared to my previous gmc that i owend. I replaced the front brake pads which didnt really need it and back ones couldnt get the t-55 bolts out for nothing. Brakes are just as spongy as before. Idk if there is air in the lines or if chevys brakes are just spongy.
I ended up having to take it in..they put new disc and pads on rear and fronts were ok...Brakes are spot on now..Hardly have to press them down now...Thats how i like them.