Community Forums

trebot · 03-15-2018, 03:55 PM

New unit to me. Just bought '07 Itasca. I don't know what oil is in motor. Thinking of changing to Full Synthetic (Quaker State 5W30). Any harm with residual oil left in motor at change? Is the viscosity right, 5W30? Thanks

WA Larry · 03-15-2018, 06:00 PM

I would opt for a "high mileage" oil. I've gone to these, regardless of mileage, because they have additives to conditions seals where age is more of a factor than mileage. Not too bad of a price by the gallon at Walmart or even through Amazon Prime.

Regular new full synthetic oils can often result in new oil leaks because they clean so well that they can remove the gunk assisting the old, tired seals hold oil in.

5W-30 is probably right, but check the oil cap, stickers under the hood, or a chassis manual to know for sure.

gruelens · 03-15-2018, 06:12 PM

I also have an '07 Workhorse with the 8.1 gasser V-8. IMO using full synthetic oil in the engine is a "no brainer". I personally use Mobil 1 in the 5-30W. The engine comes stock with a 1 pint capacity oil filter. I would recommend the 1 quart or 2 quart replacement oil filter. Using the search window at the top of each page will reveal lots of info about that. All the best.

Arch Hoagland · 03-15-2018, 08:58 PM

I use Mobil 1 good for 15,000 mile oil sold at Walmart. I still change at 3000 to 4000 miles but like the extra protection.

I run 10/30 weight and buy my PF454 oil filter at the Chevrolet dealer. 5/30 is recommended.

Don't worry about previous oil.

vsheetz · 03-15-2018, 10:55 PM

I've used mobile 1 full synthetic in all gas engines for many years.

Yosemite77 · 03-16-2018, 06:23 AM

I had a 2005 Suburban 2500 with the 8.1 engine. When I switched to synthetic oil, a leak I had in the oil cooler lines became noticeably worse. I replaced the lines and switched back to High Mileage oil.

70ChevelleSS · 03-16-2018, 07:06 AM

I use Mobile 1 in everything except my 1070 Chevelle. I use WIX filters on everything. There is no problem with any old, residual oil. They are fully compatible, you can use half synthetic and half conventional oil if you wanted to. You can go with a larger filter but first check the micron filtration specs. Some don't filter as well as the recommended filter for that engine.

dieselclacker · 03-16-2018, 07:40 AM

Your profile lists Florida as your home state. Given the climate there, I would opt for 10W/30 viscosity oil. There is a temperature/viscosity chart in the front portion of your owners manual

harleyjt · 03-16-2018, 11:53 AM

I'm using the Mobil 1 5w30 as well. I also use the 2 qt oil filter that gives me a total of 8 qt capacity. AC Delco has one as does NAPA.
jt

CJ7365 · 03-16-2018, 06:37 PM

Quote:

Originally Posted by Yosemite77

I had a 2005 Suburban 2500 with the 8.1 engine. When I switched to synthetic oil, a leak I had in the oil cooler lines became noticeably worse. I replaced the lines and switched back to High Mileage oil.

Just curious how many mile do you have on your Suburban?

Yosemite77 · 03-17-2018, 07:00 AM

Quote:

Originally Posted by CJ7365

Just curious how many mile do you have on your Suburban?

When I sold it I think it was around 115,000.

coopcolt · 03-17-2018, 07:44 AM

I have always used Mobil 1, 10w30, as 98% of my driving is
40 to 90 degrees. And for a dozen yrs. a 2 qt. Wix filter from
www.filter1.com...free shipping orders over $50.00.
Wix oil filter for 8.1, 51794 price in Jan. was $10.58...coopcolt

udid · 03-22-2018, 02:42 AM

Quote:

Originally Posted by harleyjt

I'm using the Mobil 1 5w30 as well. I also use the 2 qt oil filter that gives me a total of 8 qt capacity. AC Delco has one as does NAPA.
jt

The extra oil serves no purpose given the extra oil will always remain in the filter at any given time. Save your money.

Steve N Sal · 03-22-2018, 02:58 AM

I've used only Mobil 1 in ours since purchasing it back in 08. Don't know what the previous owner used. I change the oil every 3-4 thousand miles. That engine works hard so the extra protection in my mind is only a good thing. Enjoy your new to you coach and be safe.