Jump to content

Vote for Tractor of the Month
Garden Tractors and Parts on eBay

- - - - -

And todays debate is on fueling up and oil changes in our GTs

  • Please log in to reply
32 replies to this topic

#31 olcowhand OFFLINE  


    Red Tractor Nut & Diesel Addict

  • Staff Admin
  • Staff
  • -GTt Supporter-
  • Sponsor
  • Contributor
  • Member No: 20
  • 35,254 Thanks
  • 29,702 posts
  • Location: South Central Kentucky

Posted October 04, 2015 - 08:54 PM

I've been using 15W40 in everything from 150HP V8 tractors, all the way down to 6hp small engines for the last 25 to 30 years.  This has served me well.  Might be "wrong", but it works.  Lots easier too, as I keep only one grade of motor oil.

  • Cvans, backwoods and EricR have said thanks

#32 Cvans OFFLINE  



  • Senior Member
  • -GTt Supporter-
  • Member No: 5412
  • 4,345 Thanks
  • 4,936 posts
  • Location: Eastern SD.

Posted October 04, 2015 - 11:41 PM

Daniel it's interesting you have had good luck with one oil. Last year I thought I would do the same thing. I put Cennex 15-40 in the 850 Ford tractor and for the first time since I've owned it I've had to add oil and it is smoking out of the crankcase breather. I've decided that there will be no more Diesel oil in the gas engines. Maybe Rotella would be different, I don't know. 

  • olcowhand said thank you

#33 1oldbuzz OFFLINE  

  • Senior Member
  • Member No: 61298
  • 254 Thanks
  • 243 posts
  • Location: Manitowoc WI

Posted October 05, 2015 - 03:17 AM

Couple comments

Zinc is and would be of concern in a High HP or High valve spring pressure engine

and its intended purpose was to help prevent premature cam lobe failure.

Everything built today is Roller cams no need for zinc

also unless you a puller your not going to have high spring pressures


Lead was in fuel to aid in the cooling of the valves and eventually lead to deposits on the exhaust valve thus holding the

valve open and loss of compression

the fix was to have rotators on the exhaust valve to rotate the valve to GRIND off the deposits which lead to recessed and burnt valves

But unleaded fuel was the blame for this and the fix was hardened valve seats


And as far as diesel oils they too have less zinc as they also have been changing up to roller cams


And with gas I spend the extra for real gas and it gets treated with stabil its cheaper in the end

Edited by 1oldbuzz, October 05, 2015 - 03:18 AM.

  • Cvans and backwoods have said thanks