Which kind amsoil should I use for my diff?

So I go to my local Store and they had about 3 different bottles.long story short after 10minutes trying to decide I ended up walking out with the Severe gear 75w-90 was that the right choice?

id use lightweight non-shock.. but there are about 20 threads on this already.

Um they don't list any of theyr oils as lightweight non shock could someone show me a picture of the bottle?

the owners manual states that an SAE 90 Viscosity hypoid gear oil, API service classified GL5 or GL6 only, in the differential.

i use a 75-90 weight oil here in the northeast, i believe the northern states and canada like to use this weighted oil but i'm sure you can be fine with a 80-90 or straight 90 weighted oil. The first figure is more important to determine how the oil behaves when cold, so in cold weather on cold starts a 75-90 oil will be lighter than a straight 90.

correction: it's not the most important figure the 90 is the more important number....sorry.

sorry, thats a redline oil.

i have never used amsoil gear oil, but check the FAQ there is alot of info already out there.

order the straight 90 from hard top guy

75W140...

Use the Severe gear 75/110 or 75/140 the 75/90 is ok but, the 75/110 is better.

Blaspheme!

Blaspheme!

Thou Shalt Not Use Anything Else Than Mobil1 75W-90!
Its Written In Stone!


J/k.

I just put in the Amsoil 75w-110 Sever Gear oil, I highly recommend this viscosity. It is smack dab in the middle and higher end of the SAE 90 Viscosity range in hot temps (which Honda recommends) yet it has superior cold flow properties over an actual SAE90, which gets the diff. lubricated faster in cold weather. A perfect match for our diff. My car had Redline 75w-90 in it when I got the car, many of the 75w-90 fluids out there are on the lower end of the SAE90 viscosity range in hot temps. I'd prefer to be in the middle to upper range of the SAE90 spec as my personal preference. A lot of the numbers are confusing, but when you look at actual viscosity numbers and compare them to an SAE90 spec range it makes it easier to choose a fluid type. Here is a great link to viscosity charts:
http://www.bobistheoilguy.com/index.php?op...id=48&Itemid=55

The SAE90 hot temp spec range is approx. 14 to 24 Cst 100degree Kinematic range viscosity. Amsoil 75w-100 Severe Gear gives you a 100 degree Cst Kinematic viscosity of 20.4. Many 75-90 fluids are in the 16 kinematic cst 100 degree temp range, which is the lower part of the spec range. Keep in mind at hotter temps the difference is even more important.

Check out the SAE90 gear oil spec range in the link above. Then get the viscosity info from your favourite fluid manufacturer's website. Compare them to the chart to see if it is going work for you or not. The Amsoil 75w-110 Sever Gear oil fits the spec perfectly IMO, I won't use anything else as we need good cold weather flow combined with good hot weather viscosity protection and this provides is spot on.

This post has been edited by JFUSION on Nov 8 2009, 10:04 AM

Some are doing their research
To bad they have missed an important thing.
SAE J306 spec was changed.
That's all I'm saying.
Because it's all, and I really mean ALL, been said before.
Nevertheless: 75W-110 and 75W-140 are IMO much better than the popular 75W-90 oils.

ah yes, thanks for the correction on the spec change, though I still believe the 75w-110 weight is the perfect fluid for the best of both worlds, hot and cold weather performance.

Ok cool thanks for all your help

i see, said the blind man....lol, but i also see that 75/140 is overkill for our 4.10 final gear, don't ya think, "possibly resulting in poor fuel economy or shift problems"

"The need for redefined classifications centered on the wide variation in kinematic viscosity possible for SAE 90 and SAE 140 grade lubricant. In the prior version of SAE J306, these ranges were so broad that lubricant viscosity could vary greatly and still technically be in grade. Two new viscosity grades were introduced to cover the upper end of the specifications, SAE 110 and SAE 190. The more narrowly defined classification provides OEMs with greater flexibility in specifying a viscosity grade to ensure an optimal balance of fuel economy and durability for their equipment.

In addition, under the old designations, an axle could be serviced with a lubricant having a viscosity significantly lower or higher than the lubricant with which the axle was validated. To prevent the axle from being filled with a lubricant with too low a viscosity, an OEM was forced to specify a higher viscosity grade than actually desired.

For example, under the old classifications, if the optimum 100°C viscosity for an axle was 19.5 cSt, the OEM would normally specify an SAE 90 lubricant. However, the actual viscosity of this lubricant could be as low as 13.5 cSt, which might be too low to provide the required durability. To prevent this problem, the OEM would recommend an SAE 140 grade lubricant, ensuring that viscosity would never fall below 19.5 cSt. Unfortunately, that also means viscosity could be as high as 41.0 cSt, possibly resulting in poor fuel economy or shift problems. Under the new limits, the OEM would recommend SAE 110 grade lubricant, which meets the 19.5 cSt requirements and ensures that the axle is serviced with a lubricant having a viscosity no higher than 31 cSt.

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A Question of Balance

OEMs are challenged today to meet the often conflicting demands for improved fuel economy coupled with improved axle durability. Government regulations are dictating better fuel economy, while vehicle owners are demanding increased performance. Engine horsepower has increased by 34% over the last decade, but axle gear sizes have remained constant, sump capacities have been reduced, and drain intervals have been extended. These demanding conditions can be met only by axle lubricants that provide enhanced durability protection.

Axle efficiency can be improved by using lower viscosity fluids (such as SAE 75W-90), which minimize frictional churning losses. However, light trucks and SUVs are often used in conditions that expose axles to heavy loads or high operating temperatures. These conditions require superior axle protection, often provided by choosing a heavier viscosity fluid (SAE 75W-140, for example). Commercial vehicle applications may have even more stringent durability requirements. However, providing high durability and long vehicle life often reduces fuel efficiency.

The new viscosity classifications provide more flexibility for OEMs to select the optimum viscosity grade for an application. For example, the SAE 110 grade should be useful in an SUV or light duty truck where improved fuel economy is important but high torque or durability at high speed operation is essential. This new classification should aid OEMs in specifying a fluid viscosity more tightly to ensure that the lubricant has the intended physical properties for a given application.

The SAE 190 grade may allow better efficiency and enable multigrade performance in severe duty applications where high film strengths are needed. These end uses may include applications such as construction equipment operated in extreme temperature environments. The end result is a better match of fluid performance to axle needs.

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Your Labels May Need To Change

The revised SAE J306 may cause some labeling issues in the marketplace. Lubricants should be labeled according to the guidelines of the revised standards. The problem is that lubricants blended to the high end of the old ranges may be on the market labeled as SAE 90 or SAE 140, when they are really SAE 110 or SAE 190 lubricants. Lubricant manufacturers should examine their records and adjust their labels to reflect the viscosity ranges described in the updated SAE J306 standard."


http://www.lubrizol.com/DrivelineAdditives...ifications.html