Oil Additives

[tbone1004]

I've got a query out to Royal Purple for ZDDP as well

[MSeriesRebuild]

I've got a query out to Royal Purple for ZDDP as well

I don't know why, but Royal Purple has the poorest dealer network and supply chain I've ever dealt with. That's the main reason we stopped using their products, could never get anything in a timely fashion, I'm talking weeks and months to get the most simple orders. Not worth the hassle, Amsoil has what I've found to be better products at a better price, and I can get anything they offer delivered to the shop door within 3-4 days or less.

[tbone1004]

interesting. We have great service through our distributor, AES Seal, but we buy a lot of industrial lubricants through them and they're really responsive. Was really interesting talking to some of their engineers at the Power Gen show about the use of straight weight engine oil in the transmissions and xfer cases and why not to use it since a 15w50 engine oil is the same viscocity as a 75w90 gear oil but the gear oil obviously has better shear responses. May be making the switch to amsoil as I still have to switch over my tranny, xfer, and diff oils.

[MSeriesRebuild]

I don't know any trans builders that recommend gear oil these days, that is designed for differentials. The heavy truck gear boxes of today all recommend a straight grade 30, 40, or 50 weight depending on ambient temps. All the higher end oil producers offer oils in these grades that are designed especially for transmission use. Specs and lubricants are constantly changing along with gear box technology. The days of heavy oil specs in trans and t/case applications are fading fast. Heavy oils don't lubricate as well, don't circulate readily in cold temps, cause harder shifting, cause a gear box to operate at higher temps in summer conditions, and are bad for fuel economy. In short, the lighter the oil that will properly lube the box, the better it is in all aspects is what we are being told from all the major trans manufacturers whose products we use.

Because a 65 year old manual says use 90 weight does not mean that a better product does not exist today. Back then it was 30 weight in the crankcase and 90 weight in the gear boxes. What one must realize is that back then, that is virtually all there was. Today we can search a variety of products and grades, choosing the lubricant that best serves your application and operating conditions.

We used to deal with a Royal Purple industrial lubricants dealer (Atlan-tech) to source our oils and grease. It got to where corporate would not let them deal automotive products to us since they were an industrial supplier. We then tried to contact automotive Royal Purple suppliers, no luck. None were able to source many specialty products that we used. We used a lot of straight grade 40 weight oil, which they dropped from their line and do not offer at all anymore. Could never get anything but a run around, they would argue over what was an industrial or automotive product and who could supply it. It got utterly ridiculous. We bought thousands of dollars worth on single orders, they acted as if they couldn't care less. I don't have to deal with folks like that, so I simply went elsewhere, and I'm glad I did. I think Royal offers a good product, but it doesn't matter how good it is if no one can or will supply it.

[tbone1004]

what I was saying wrt the oil weights is that a 50w motor oil is identical viscosity to a 90 weight gear oil at the same temperature and the 30w oil that you recommend is a 80/85 weight gear oil. Viscosity wise a 15w50 motor oil will behave the same as a 75w90 gear oil, so as an engineer I find it quite confusing why you would put motor oil in an application where it was not designed when a comparable product designed to deal with the shear forces is already there.

I'm not trying to be combative but your first paragraph just doesn't make sense due to what I said above, and if it was true, then why is any company still making MTF? I can see a lot of the high performance tranny manufacturers starting to recommend ATF instead of gear oil because the viscosity is so low, but it still has the additives in there to protect the oil from shear that a crankcase oil isn't designed for. Very very different environments. Obviously if a transmission manufacturer is calling for motor oils in the crankcases then that is one thing, and you obviously know more about the heavy duty truck transmissions than I do, so if they are calling for motor oil instead of gear oil in straight cut gear transmissions then I'm game, and the EP additives are probably excessive, but I don't see how they can behave differently when the viscosity is the same at operating temp shown below. It would be interesting to see if ATF is suitable for these transmissions since you would see even easier shifting using a viscosity that is as low as ATF

[MSeriesRebuild]

I have the same chart and am fully aware of the viscosity cross overs. My info is what we were told by the Arvin-Meritor engineers who are now the builders of the Spicer 5-speeds we use so many of. The heavy duty motor oil specs for 30, 40. and 50 weight are straight from them. I'm not an engineer, however I am very familiar with transmissions and their wear characteristics. Have torn down many, have seen what things look like where various types of oil was used. Frankly I just don't have the time to argue, so I'll say this. My recommendations are based on the engineer's assessment and my own experience. You can make your own assessment and run anything you like.

[Chris P]

Which Amsoil oil is recommended for the M37?
-thanks

They offer several, if you will email me at mseriesrebuild@windstream.net I'll send you a list of Amsoil specs.

Email sent.
thank you

[tbone1004]

This is what I got back from Royal Purple

First choice would be our MaxGear 75w90 as it is a GL 4/ GL 5 /MT 1 rated oil for gear applications

Is inert to the softer yellow synchronizers but is made with base oils with bigger molecules than. A motor oil for better cushioning of the gear interface on this older style transmission.

Second choice would be our HPS 10w40 which contains our Synerlec additive so it has close to the EP qualities desired for the transmission gears. HPS oils are made to CI-4+/ SL API service classification so contain 1300 ppm of ZDDP - the answer to your other question posed to the AES Seal rep

In the 50's - multigrade oils were not very common.
A GL4 in that vintage was a gear oil made with bright stock base oils but had a 50% treat rate of the EP additive to reduce the phosphorus playing out on the bronze.

O

David

dcanitz@royalpurple.com


Looks like they still have engine oil with a high amount of ZDDP in there as well as making a 10w40 motor oil that is compatible with the gearboxes.


Good to know and looks like I'll have our RP rep drop off a couple cases of the HPS10w40 and try that for engine and transmission.

Thanks for the insight Charles, glad to hear it coming from the guys that are designing the things as well as the ones that are rebuilding. Was just confusing on my end hearing about "heavy" oils when the viscosity is the same.

[W_A_Watson_II]

For the NP435 Trans I run, and all the older ones I use/will use Lucas Synthetic 50 wt. Trans Lubricant. It's specially formulated to address the softer metals and not destroy them like a modern trans oil.

[Chris P]

W.A Watson,
Do you use that in your transfer case as well?

[W_A_Watson_II]

Chris, I haven't, just in the NP435 and a T-15. But is should do the job their as well. It catches you off guard when you open it up and pour it in, as it's a clear oil, no color what so ever.

[MSeriesRebuild]

This is what I got back from Royal Purple

First choice would be our MaxGear 75w90 as it is a GL 4/ GL 5 /MT 1 rated oil for gear applications

Is inert to the softer yellow synchronizers but is made with base oils with bigger molecules than. A motor oil for better cushioning of the gear interface on this older style transmission.

Second choice would be our HPS 10w40 which contains our Synerlec additive so it has close to the EP qualities desired for the transmission gears. HPS oils are made to CI-4+/ SL API service classification so contain 1300 ppm of ZDDP - the answer to your other question posed to the AES Seal rep

In the 50's - multigrade oils were not very common.
A GL4 in that vintage was a gear oil made with bright stock base oils but had a 50% treat rate of the EP additive to reduce the phosphorus playing out on the bronze.

O

David

dcanitz@royalpurple.com


Looks like they still have engine oil with a high amount of ZDDP in there as well as making a 10w40 motor oil that is compatible with the gearboxes.


Good to know and looks like I'll have our RP rep drop off a couple cases of the HPS10w40 and try that for engine and transmission.

Thanks for the insight Charles, glad to hear it coming from the guys that are designing the things as well as the ones that are rebuilding. Was just confusing on my end hearing about "heavy" oils when the viscosity is the same.

For me, I'd be cautious about putting 10W40 in the trans or t/case. What the Spicer reps have said was straight 40 weight, they have not recommended a multi grade oil that light. Based on conversations with them, I don't expect they would recommend that, although I have not asked that question specifically.

[isaac_alaska]

Went oil shopping at Napa today. Remember this is Alaska where Im not sure how to go about ordering from amsoil, they'll probably say they can't ship it to me. Their amsoil supply was low/missing most of the flavors, but they had a good deal on royal purple 15W40. Just over $7/quart, which I was happy to pay! Then drove across town to the other Napa for a filter. What's the concensus with royal purple 15w40, zinc additive or unnecessary?
Love all the information in this thread

[MSeriesRebuild]

The Zinc question is one you would need to ask a Royal Purple Rep., (one that is really in the know, not a store clerk.) As I recall when we used to work with RP, I think they were phasing it out of their main stream products like most others. The AMSOIL product that is designed for older engines with a high ZINC content is called Z-ROD. I can honestly say this is a great product; I can even tell an immediate difference in the engine sound when using Z-ROD as compared to other oils.

[isaac_alaska]

Thanks Charles. I'll see what it takes to get some. Cause it looks like my head gasket just decided to dump a bunch of coolant into my nice new oil.