Vortec 8100 8.1L

[TrentMiller]

Guys I have a gm 8.1L on a workhorse chassis, in our 35f motor home. This is a up tuned version of the 8.1 put in the 2500's. (these things do up to 500 hp in marine applications)

It has about 19k on it and the last OC i put m1 5-30 in it.

Is this the best oil for the application?
It seems to have a bit of consumption. (all 8.1's do it seems)

It's used as a tailgater during NFL and MBL seasons (chargers/padres) witch entails short trips to the stadium.

Once a year or so we put about 4k miles on it (road trip)
It also makes a few trips to the desert each year 200mi or so but it's mountain passes.

Because of it's infrequent usage and general short trips, I thought that syn would be the most appropriate.

During heavy usage the longer oci's are obviously nice, no one wants to stop to change the oil. (but i have done it, it's so easy to lift it up with the hydraulic leveling legs and just dump and refill)

I would like to use RTS 5-40 and change once every year, or perhaps regular Rotella and maby do 6 mo oci.

Obviously we spent alot of money on this coach, although it's worth practically nothing compared to what we paid, i think we'll have it for a while.

 

[bepperb]

" use RTS 5-40 and change once every year"

Sounds pretty reasonable to me.

 

[tomcat27]

yes, sounds good - make sure to change it at the end of the season, so you dont leave dirty oil in it during the off-season - as contaminents could precipitate out and also any acids could eat away at bearings.

 

[72customdeluxe]

I wouldn't worry about the consumption, as you said it's very common with the 8.1 motor. I would run the Rotella syn over the mobil

 

[OVERKILL]

Mobil Turbo Diesel Truck or Delvac 1 would be an excellent choice as well.

 

[Cotharyus]

Not to highjack here, but what sort of OCI would you recommend with RTS, M1 Turbo Diesel, or Dev.1?

 

[bepperb]

That would depend entirely on what it would be in, and what you're doing habits are.

But one year is tops for just about any oil, and 6000 miles seems on the high end, but doable, in this app.

 

[Steve S]

Even the dino HDEOs will go the distance. In San Diego the 5w part will unneeded. The RTS 5w-40 is a great oil if that is your choice look up some of the UOAs on it.

 

[TrentMiller]

Thanks guys. I've decided that i will use RTS at 7k/12mo Normal consumption is about 1/4 to 1/2 a qt every 1k So i could possibly go beyond 9k w/o problems. I will UOA at 7k/ or 12mo and see what happens!

 

[PT1]

I would use Rotella or Delvac 15w40 and change it every 5000 miles.

 

[daman]

TDT or RTS would be great in that engine.

also if you install a cooler thermostat(160-180) it'll stop using oil.

 

[dnewton3]

I'm going to say you'd be fine with a dino HDEO in 30 grade (Delo, Delvac, Rotella in 10w-30).

The 8.1L is a good engine, of later model design, and I don't know that "thicker" is "better" in this case. Especailly with shorter trips to the games, why the need for "heavier" oils?

If you're total annual OCI is around 7.5k miles or less, I expect you'd have no real "need" for synthetics, and could probably run the entire year on one OCI.

If you want the real answer, then you'll have to run some OCIs and do some UOAs with different selections.

 

[c502cid]

My experience with a 2003 8.1 BBC. I had the best results using Mobil Delvac 5w-40. Changed every 7-8k miles, about once every 10 months. Mine would use 1/2 qt in the first 3000 miles then 1/2 qt every 1500 miles after that.