Oil change interval LLY

[TATUZINHO]

New to diesels, ex chev 3500 gas, own used 2007 GMC Topkick, still under warranty. Book on LLY says 15,000 miles between change....no way i could ever go that long, Hotshot service all over carry 7K max, no trailer. Have oil life though never comes on "walking a fine line". At $120.00+ a change don't want to be changing every 3K...but this is my living so will do whatever it takes to keep eating and paying bills.
Thanks

[Mark Rinker]

I put a quick 110K on a 2004 C4500 recently. Used Mobil Delvac synthetic, and changed the oil at 10K-12K intervals. Usually the oil change indicator came on right about the time we were ready to change, or shortly after the change. My advice is select a good synthetic oil and follow the indicator...your loads are well within range, we towed boats which are both heavy and a huge wind drag...

If you can't sleep at night - go 6K-8K - but I'd still use a good synthetic over conventional.

More importantly, use a good synthetic rear gear lube, and keep that stuff changed frequently. I let the first pumpkin full of Royal Purple (read "Royally Expensive") go for about 80K and what came out was stinky and overdue. I would say 50K intervals are in order, out back.

[Dirtbikindad393]

I use Amsoil and do 15k OCI on my 2005 LLY. If your interested in using Amsoil send me an email dirtbikindad@aol.com I can help you with the synthetics and extended change intervals.