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Topic: Full synthetic oil (Read 487 times) previous topic - next topic

Full synthetic oil

I switched to 5-40, Rotella full synthetic and added a cetane booster to the fuel before my trip this week. Pulling a 5000 lb trailer, The Cummins just purred there and back. I'm convinced it has more power and oil pressure is quicker upon start up. I've been using the cetane booster for several years so the only change was the oil.
Very happy!
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: Full synthetic oil

Reply #1 –
Why did you go with 5w40 instead of 15w40,the 5 is probably the better mileage.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Full synthetic oil

Reply #2 –
I have run the T-6 for years and use it in everything. The M11, the generator, and the hydraulic system.
No issues.
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: Full synthetic oil

Reply #3 –
I had the T-6 5-40 in stock for my pickup in the winter.
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: Full synthetic oil

Reply #4 –
just an observation....To change over to full synthetic is would cost me just over 800 bucks Canadian for the oil alone. Amazon has the oil for 82 bucks CDN per gallon. My M11 holds 38 quarts.
Is synthetic really worth it?
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: Full synthetic oil

Reply #5 –
Quote from: Peter –
just an observation....To change over to full synthetic is would cost me just over 800 bucks Canadian for the oil alone. Amazon has the oil for 82 bucks CDN per gallon. My M11 holds 38 quarts.
Is synthetic really worth it?

IMO, NO. Dino oil in your engine, as long as changes annually/based on miles is fine.

Said another way, you will NEVER wear out your M11 because of using quality dino oil. Shell Rotella T or Delo 400 are very popular and quality dino oils.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Full synthetic oil

Reply #6 –
thank you for the (less money!) explanation!
Peter
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: Full synthetic oil

Reply #7 –
Everyones money situation is different,for me the Amsoil is well worth it,with a bypass filter and their signature series oil I can
go 20k miles on a 8,3 with over 200k miles,engine never got over 205 degrees with the retarder,yes Brett is correct you will
never wear your engine out but it will run a little better with synthetic oil.If you need more info,contact John Haygarth,he is a
Amsoil user in Canada.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Full synthetic oil

Reply #8 –
I paid $19 a gallon 5 years ago
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: Full synthetic oil

Reply #9 –
One of the benefits of changing engine oil is to get rid of contaminants, so most feel that it is fine to use better oils, but they do not necessarily extend oil change intervals.  This is not the same for transmissions, etc as better oils can extend the useful life.

Re: Full synthetic oil

Reply #10 –
I change oil at 5000 miles.
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: Full synthetic oil

Reply #11 –
Reply to number 9,that's why some of us install a bypass filter,goes down to 1 micron and adds a couple of quarts to the system,
and no it does not effect oil level.
96 U270 BUILD 4810
85 380SL
Drummonds TN.