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| | | | Joined: Sep 2010 Posts: 575 Shop Shark | | Shop Shark Joined: Sep 2010 Posts: 575 | I'm pretty sure I've read every post on this forum about oil in the rear axle.
Here's what I gathered - if its got good seals (all new now) then I'm ok with 80W90, but otherwise I should use 90wt (Pure 90 - I'm guessing its more viscous?)
The post that I read that concerned me mentioned that heavier duty trucks should use the heavier oil. Mines a 1 ton - what do the other 1-tons guys use?
| | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | I use the 80W90 in mine. The writing on the bottle leads me to believe that it is good for much heavier trucks too. | | | | | Joined: Jul 2009 Posts: 23 Wrench Fetcher | | Wrench Fetcher Joined: Jul 2009 Posts: 23 | I've been selling oil for 30 years and your right truckernix, 80/90 is used in some big rigs. Most big rigs use 85/140, but small trucks and cars have been using 80/90 for many years now. I havent sold any straight 90 for at least 20 years, dont even carry it anymore. | | | | | Joined: Sep 2010 Posts: 575 Shop Shark | | Shop Shark Joined: Sep 2010 Posts: 575 | Thanks for the advise - I filled it up with 80W90 and so far no leaks. Quite the contrast in the color of what I drained out, vs what I put in! | | | | | Joined: Feb 2004 Posts: 29,886 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,886 | I've been using 85W-140 in all my vehicles, cars and trucks, for many years. The "W" stands for "winter", and the flow rate is measured at zero degrees, Farinheit, I believe. It just flows a little better and lubricates well at very low temps. 90 weight and similar straight viscosity oils get as gummy as molasses as the temperature drops, adding a lot of drag and not doing a very good job oif lubricating bearings.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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| | | | | Joined: Jan 2008 Posts: 4,964 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 4,964 | We use 80w140 synthetic in all our rear ends. Back before synthetic multigrades, it was common for straight 90w to get so thick when the temp got to around -20° Fahrenheit that the gears slung the grease away from themselves and the gears would run dry. I have seen the the whole third member turn cherry red and of course it was ruined. | | |
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