Synthetic Gear Oil

JK's JK

JK's JK

Banned
Hi Guys,

I'm going to be swapping out gears and trying to figure out the gear oil.

So the brands that have been suggested to me is

-Royal Purple 75w90 Synthetic Max Gear Oil around $19
-Red Line Synthetic Max Gear Oil around 15.50
-AMS Oil Severe Gear around $14.50
EDIT*** ---Lucas SAE 80w90 Gallon $38

All 75w90.

The guy at the gear shop sells the AMS but never heard of them.

Thoughts????
 
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All my fluids are Amsoil. Its top notch stuff. If you tow alot go with 75-140 in the rear diff. Im surprised you have never heard of it. Its very well known.

Sent from my SAMSUNG-SGH-I896 using WAYALIFE mobile app
 
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JK's JK said:
Hi Guys,

I'm going to be swapping out gears and trying to figure out the gear oil.

So the brands that have been suggested to me is

-Royal Purple 75w90 Synthetic Max Gear Oil around $19
-Red Line Synthetic Max Gear Oil around 15.50
-AMS Oil Severe Gear around $14.50
EDIT*** ---Lucas SAE 80w90 Gallon $38

All 75w90.

The guy at the gear shop sells the AMS but never heard of them.

Thoughts????
Click to expand...

If you're swapping out gears, run some cheap 75w90 during the 500 mile break in period, then go with a good synthetic. I run Royal Purple, found it on ebay for $16 a quart no tax no shipping.:beer:
 
If you check it out, most of the oils and fluids say on the back " meets or exceeds minimum requirements " they are pretty much the same and a lot of the oils are made by the same company.... You would be surprised what parts and fluids are the exact same thing with a different name. Federal mogual makes all gaskets "fel pro" all suspension and bearings " moog" "precision" and " national" it goes the same for oils
 
If you have limited slips or in some cases lockers, it may call for strictly a conventional oil. Most Synthetics have more lubricity and may be to slippery for the diffs to lock up. That's how it is for detroit lockers and/or Truetracs.
 
I put the Amsoil 75-90 severe gear in at 10,000 when I changed all the fluids. Of course the engine oil had been changed several time before that. Transmission got synchromesh, and the transfer got synthetic ATF-4.
 
If you have an ARB, ARB recommends NOT using a synthetic that includes a limited slip modifier. The limited slip modifier is an abrasive fluid that will eventually wear the ARB seals allowing fluid to enter sealed parts of the locker. I use standard Pennzoil 80W-90.
 
billybob990 said:
If you check it out, most of the oils and fluids say on the back " meets or exceeds minimum requirements " they are pretty much the same and a lot of the oils are made by the same company.... You would be surprised what parts and fluids are the exact same thing with a different name. Federal mogual makes all gaskets "fel pro" all suspension and bearings " moog" "precision" and " national" it goes the same for oils
Click to expand...

Not true, your statement is only partially correct. Just because one manufacturing facility produces all fluids, parts, brake pads, coil springs, whatever....does not mean that all items being turned out are of equal quality. Different buyers have different profit margins, price points and customer bases. For example, Eibach springs probably produces 75% or more of all coil springs on the market. So the top shelf springs being bought by King and Fox from Eibach are completely different specifications than thecrap springs Rough Country is buying from Eibach. This holds true for gaskets, brake pads, and yes, oils too. If you truly think the pep boys weekly special on 4qts of Dino 10w-30 for $8.99 that comes from the same refinery, is the same quality as the Amsoil, Royal Purple, Mobil, Quaker State, Castrol coming out of that refinery.......I wish you luck with your engine life :)

You absolutely get what you pay for when buying lubricants.
 
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Just my 2cents, if you run a Detroit locker, DON't run Royal Purple! It causes 3 times more clanking and popping from a locker than I care for. Some of their products may be good but a no go for me on the diff. Also , when RP gear oil drains out and isn't much thicker than water doesn't give me much faith in the product. Especially for diffs. I run Lucas heavy duty in both diffs with no issues. To me gear oil is pretty much gear oil, unless u need an additive for limited slip.
 
mkjeep said:
....... I run Lucas heavy duty in both diffs with no issues. To me gear oil is pretty much gear oil, unless u need an additive for limited slip.
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yep, since I live in a state that's only 4 blocks from the core temperture of hell itself, I too run Lucas gear oil- HD 85w-140. It's thick, it's awesome and worth it.
 
JK's JK said:
Hi Guys,

I'm going to be swapping out gears and trying to figure out the gear oil.

So the brands that have been suggested to me is

-Royal Purple 75w90 Synthetic Max Gear Oil around $19
-Red Line Synthetic Max Gear Oil around 15.50
-AMS Oil Severe Gear around $14.50
EDIT*** ---Lucas SAE 80w90 Gallon $38

All 75w90.

The guy at the gear shop sells the AMS but never heard of them.

Thoughts????
Click to expand...

Just buy Mobil1 for $10. Wasting money with the rest. If you want to splurge, buy Amsoil.
 
GCM 2 said:
Not true, your statement is only partially correct. Just because one manufacturing facility produces all fluids, parts, brake pads, coil springs, whatever....does not mean that all items being turned out are of equal quality. Different buyers have different profit margins, price points and customer bases. For example, Eibach springs probably produces 75% or more of all coil springs on the market. So the top shelf springs being bought by King and Fox from Eibach are completely different specifications than thecrap springs Rough Country is buying from Eibach. This holds true for gaskets, brake pads, and yes, oils too. If you truly think the pep boys weekly special on 4qts of Dino 10w-30 for $8.99 that comes from the same refinery, is the same quality as the Amsoil, Royal Purple, Mobil, Quaker State, Castrol coming out of that refinery.......I wish you luck with your engine life :)

You absolutely get what you pay for when buying lubricants.
Click to expand...

Agree with your post, but to a point. The bold in particular. Just because the product is expensive, doesn't mean it's any good (Royal Purple is an example) and consistently performs worse than big box no name oil, let alone quality synthetics like Mobil1, Amsoil, etc. I've posted all the data in various oil threads on here, but the cliff notes for fluids are simple...

Go to your local big box store, find the fluid you want, and buy the lowest priced QUALITY BIG BRAND fluid (Castrol, Valvoline, Mobil1, etc.) Royal purple performs WORSE than them all, and costs a considerable amount more. Mobil1 is usually the cheapest of them all, especially if you buy in larger containers (like the 5 quart jug at walmart) or in bulk (6 quart case at costco). If you want the best fluid, Amsoil is it, but for over the counter, Mobil1 is usually the best, and usually the cheapest as well.
 
NFRs2000NYC said:
Agree with your post, but to a point. The bold in particular. Just because the product is expensive, doesn't mean it's any good (Royal Purple is an example) and consistently performs worse than big box no name oil, let alone quality synthetics like Mobil1, Amsoil, etc. I've posted all the data in various oil threads on here, but the cliff notes for fluids are simple...

Go to your local big box store, find the fluid you want, and buy the lowest priced QUALITY BIG BRAND fluid (Castrol, Valvoline, Mobil1, etc.) Royal purple performs WORSE than them all, and costs a considerable amount more. Mobil1 is usually the cheapest of them all, especially if you buy in larger containers (like the 5 quart jug at walmart) or in bulk (6 quart case at costco). If you want the best fluid, Amsoil is it, but for over the counter, Mobil1 is usually the best, and usually the cheapest as well.
Click to expand...

Agree completely, some things do get marked up without regard to comparative performance. But most of the time, quality does come at a higher premium :rock:
 
I couldnt agree more than with the $8 comment.
I dunk the axles in water... no problem.. I change the oil.
the diff cover starts leaking...no problem. reseal and change the fluid.
you hear a wierd noise.. no problem. pop the cover and look..change the fluid.

the point is, I change the fluid enough whether I want to or not that makes no sense at all the use expensive gear oil.
you pull junk yard axles with 400000 miles on them and the original gear oil. you pop the cover and the axle looks brand new inside (and smells horrid)
 
GCM 2 said:
Not true, your statement is only partially correct. Just because one manufacturing facility produces all fluids, parts, brake pads, coil springs, whatever....does not mean that all items being turned out are of equal quality. Different buyers have different profit margins, price points and customer bases. For example, Eibach springs probably produces 75% or more of all coil springs on the market. So the top shelf springs being bought by King and Fox from Eibach are completely different specifications than thecrap springs Rough Country is buying from Eibach. This holds true for gaskets, brake pads, and yes, oils too. If you truly think the pep boys weekly special on 4qts of Dino 10w-30 for $8.99 that comes from the same refinery, is the same quality as the Amsoil, Royal Purple, Mobil, Quaker State, Castrol coming out of that refinery.......I wish you luck with your engine life :)

You absolutely get what you pay for when buying lubricants.
Click to expand...

mkjeep said:
Just my 2cents, if you run a Detroit locker, DON't run Royal Purple! It causes 3 times more clanking and popping from a locker than I care for. Some of their products may be good but a no go for me on the diff. Also , when RP gear oil drains out and isn't much thicker than water doesn't give me much faith in the product. Especially for diffs. I run Lucas heavy duty in both diffs with no issues. To me gear oil is pretty much gear oil, unless u need an additive for limited slip.
Click to expand...

GCM 2 said:
yep, since I live in a state that's only 4 blocks from the core temperture of hell itself, I too run Lucas gear oil- HD 85w-140. It's thick, it's awesome and worth it.
Click to expand...

NFRs2000NYC said:
Agree with your post, but to a point. The bold in particular. Just because the product is expensive, doesn't mean it's any good (Royal Purple is an example) and consistently performs worse than big box no name oil, let alone quality synthetics like Mobil1, Amsoil, etc. I've posted all the data in various oil threads on here, but the cliff notes for fluids are simple...

Go to your local big box store, find the fluid you want, and buy the lowest priced QUALITY BIG BRAND fluid (Castrol, Valvoline, Mobil1, etc.) Royal purple performs WORSE than them all, and costs a considerable amount more. Mobil1 is usually the cheapest of them all, especially if you buy in larger containers (like the 5 quart jug at walmart) or in bulk (6 quart case at costco). If you want the best fluid, Amsoil is it, but for over the counter, Mobil1 is usually the best, and usually the cheapest as well.
Click to expand...

This is the information that I needed to know about gear oil. Lucas is the way I'm going now.

What about Trans fluid?
 
JK's JK said:
This is the information that I needed to know about gear oil. Lucas is the way I'm going now.

What about Trans fluid?
Click to expand...

This is an item I also run high end lubricants in, especially if you are running larger tires, off roading pretty hard, basically just doing what we bought our jeeps to do. In my hellishly hot home state of Arizona, cars overheating are not the biggest problems unde the hood, transmission failures lead the pack. Driving my overweight jeep on 40"s in 110+ temps around town during the summer is brutal on the transmission. I will only run top name fluids like Mobil, Amsoil, etc. The last change I did at 28,000 miles (added a new deep sump skid pan, so I swapped fluids too) I used Amsoil.
 
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