corn head grease
- Thread starter sonny
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FlatheadTed
Well-known member
Is the big truck is noisy ?
rotorwrench
Well-known member
The folks selling 600 gear lube don't always specify what the blend is or if it ia an actual steam cylinder oil. The 600 grade was pre-SAE so the viscosity is a mystery unless specified some where on the container. Macs was recently purchased by another resto parts vendor corporation so it will take a while to see how the products improve or suffer due to the change.
If it is a late type multi viscosity lube, it will appear to be less viscous due to the polymers added for cold weather operation. I wouldn't advise using anything but one straight grade gear lube in the transmission. If you can find GL4 SAE 90 gear lube, it should stay in there. I wouldn't go over SAE 140 grade or it could get harder to shift. You shouldn't have lost a quart if the transmission remained level while installed. If the nose droops down then it will leak out around the main input shaft slinger ring over a period of time. Some transmissions have seals for the main input and some don't.
If it is a late type multi viscosity lube, it will appear to be less viscous due to the polymers added for cold weather operation. I wouldn't advise using anything but one straight grade gear lube in the transmission. If you can find GL4 SAE 90 gear lube, it should stay in there. I wouldn't go over SAE 140 grade or it could get harder to shift. You shouldn't have lost a quart if the transmission remained level while installed. If the nose droops down then it will leak out around the main input shaft slinger ring over a period of time. Some transmissions have seals for the main input and some don't.
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David J
Well-known member
No I have not . You should note that cornhead grease is urea based . Make your own call on the compatibility of that with normal gear lube but from what I've found I will definitely Not be doing it .
Uncle Bob
Well-known member
rotor has a pretty good handle on the picture of gear lubes, but I'll add a couple more remarks.
"Thickness" doesn't equal lubrication.........yeah, this is the USA, but "more is better" doesn't always apply.
Keep in mind, grease is composed of three major component classes; lube oil, thickener, and additives. It's the lube oil part that does the lubrication, the thickener that holds it in place (why grease is most often spec'd for applications with poor sealing/containment), and additives to supplement the performance of the oil constituent.
Corn head grease is usually a 0 grade (look up NLGI grease grades if you're intellectually stimulated), which is soft in grease terms, which means it's got a comparatively small amount of thickener in it. One responder mentioned urea, that's in reference to the thickener, not the oil component. JD uses a polyurea thickener, but Cenex has a corn head grease also, and they use lithium based thickener. The oil component of the Cenex product is about the same viscosity grade as an SAE 30 motor oil, which is about an SAE 80 gear oil specification. On a quick look I couldn't find any oil component viscosity data on the JD product, but I'd guess it's similar.
Edit, had to correct the vis info in the last paragraph as I fubared my reading of the chart when in a hurry.
"Thickness" doesn't equal lubrication.........yeah, this is the USA, but "more is better" doesn't always apply.
Keep in mind, grease is composed of three major component classes; lube oil, thickener, and additives. It's the lube oil part that does the lubrication, the thickener that holds it in place (why grease is most often spec'd for applications with poor sealing/containment), and additives to supplement the performance of the oil constituent.
Corn head grease is usually a 0 grade (look up NLGI grease grades if you're intellectually stimulated), which is soft in grease terms, which means it's got a comparatively small amount of thickener in it. One responder mentioned urea, that's in reference to the thickener, not the oil component. JD uses a polyurea thickener, but Cenex has a corn head grease also, and they use lithium based thickener. The oil component of the Cenex product is about the same viscosity grade as an SAE 30 motor oil, which is about an SAE 80 gear oil specification. On a quick look I couldn't find any oil component viscosity data on the JD product, but I'd guess it's similar.
Edit, had to correct the vis info in the last paragraph as I fubared my reading of the chart when in a hurry.
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KGS
Well-known member
No I have not . You should note that cornhead grease is urea based . Make your own call on the compatibility of that with normal gear lube but from what I've found I will definitely Not be doing it .
I've heard the urea base comment before. What would be the problem with it?
I've heard the urea base comment before. What would be the problem with it?
FlatheadTed
Well-known member
I think trucks should have or were specified 120 to 140 grade lube.
David J
Well-known member
Uncle Bob is right about the polyurea being a thickener and the fact it is a relatively thin grease so it has a smaller amount of thickener . As far as problems with it I'm not an engineer and the tech stuff is pretty in depth on this but what is consistent is the listing of the incompatibility of conventional polyurea based and lithium based grease .Not in the borderline or compatible categories . One of the worst case scenarios described was a chemical reaction between the two with the end result of " balling up " of the grease with little lubrication going on . I would assume this means lumping up and no longer getting into all the needed places . I am not demonizing the JD stuff and as you can see I buy it by the case . Wonderful stuff where it belongs and also in the steering heads of my unstyled JD tractors . I also didn't have a lot of success finding the minute details of this stuff but the dropping point is easy to find = 450*F . That is not low in my book . Before he tried of this subject Ed Solari talked of these issues and he IS an engineer . As always I'm willing to listen to GOOD info as I definitely don't know it all but the two being incompatible is pretty easy to find on the net if you wanna look . That's good enough for me .
