oil weight
Outstanding HDF Member
Joined: Mar 2008
Posts: 2,306
Likes: 39
From: Everywhere
Originally Posted by hotrod351
dont think i can go to auto parts and grab a quart of amsoil off the shelve. maybe i just buy HD brand.
Ultimate HDF Member
Joined: Dec 2009
Posts: 5,865
Likes: 168
From: Potsdam, NY
All multigrade oils are made from a single weight base oil + an additive package. Single weight base oils will have there viscosity within a certain set range at different temperatures. All oils get thinner or have reduced viscosity as tempature increases.
The lower number, 20W, in this case is the weight of the single weight base oil. The higher number is obtained by adding polymers, which are part of the additive package, which act with heat to keep the oil from only thinning as much as a 50W or 60W base oil as the engine runs at operating tempature.
The lower number, 20W, in this case is the weight of the single weight base oil. The higher number is obtained by adding polymers, which are part of the additive package, which act with heat to keep the oil from only thinning as much as a 50W or 60W base oil as the engine runs at operating tempature.
Road Warrior
Joined: Jul 2016
Posts: 1,370
Likes: 439
From: va
I agree with fat_tony 100% as polymers do thicken oil , in fact I use 20w/50 and addd 1 bottle of STP ( which has a lot of polymers ) at oil change in summer as told to do so by a oil co Rep , so I have my cold start and 60wt
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Grand HDF Member
Joined: May 2010
Posts: 3,599
Likes: 5,175
From: SWMO
Nothing original about that stuff. They buy from oil companies and blend. Do a little history digging. Synthetic oil was around many, many years prior to Amsoil. For example, Hitler had a big program developing and using syn oil for vehicles on the cold ***, eastern front.