Correct. 10W30 at operating temp has the same viscosity as 30W at operating temp (about 210 degrees) - when "fresh". After 100 hours of use though the 10W30 MIGHT (probably) have less viscosity than straight 30W after the same amount of use. The bigger the multiple between the "W" number and the last number the more likely the oil will break down - especially in conventional oils. 5W40 has a multiple of 8 - not nearly as stable as 15W40 (multiple of 2.67) (usually). 10W30 has a multiple of 3 and 5W30 has a multiple of 6 - the 10W30 is less likely to lose viscosity (use will lose less viscosity) than the 5W30 (USUALLY).
A lot of this also has to do with the QUALITY of the motor oil. A good QUALITY 5W30 MIGHT be able to out perform "Casey's" 10W30 that's on the shelf in the C-Mart. In my opinion 10W30 Castrol GTX is one of the best conventional motor oils you can buy - while the next guy will tell me I don't know &^%$ and it is something else.
Upload one or more videos to your post. Photo filesizes should be less than 300K and Videos, less than 2MB. Formats allowed are gif, jpg, png, ogg, mp4, mov, and avi. Be sure to use filenames without spaces or special characters, and filetypes of 3 digits lower case.
We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]
Today's Featured Article - A Lifetime of Farm Machinery - by Joe Michaels. I am a mechanical engineer by profession, specializing in powerplant work. I worked as a machinist and engine erector, with time spent overseas. I have always had a love for machinery, and an appreciation for farming and farm machinery. I was born and raised in Brooklyn, New York. Not a place one would associate with farms or farm machinery. I credit my parents for instilling a lot of good values, a respect for learning, a knowledge of various skills and a little knowledge of farming in me, amo
... [Read Article]
Latest Ad:
1964 I-H 140 tractor with cultivators and sidedresser. Starts and runs good. Asking 2650. CALL RON AT 502-319-1952
[More Ads]
All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy
TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.