Engine/Transmission (1998.5 - 2002) This is not an "oil war" question!

[Ncostello]

I have seen the oil war (almost as bad as the Gulf War itself) posts while searching for my question. Wow. It really is a heated debate without doubt. But I want to stay out of that here. My question is simple. I am not looking for comparisons or other products that will work. What works is clearly stated elsewhere. Just the facts on the brand I like.



Does Mobil 1 (synthetic) make a lube for use in the NV4500 5-speed. I have read several archive posts about lots of folks using it in differentials with luck. But I could not find one that said it was good for the NV4500 trans specifically. I would like to use it in my differential and also in the trans if possible.



Remember, Mobil 1 is the key word here... hehe.



Thanks.

 

[TPlasek]

To keep out of a war, I sent you a PM. I am rebuilding my NV4500 and have been researching almost that same question.

I just asked for ANY alternative.



I think the only way to see which one works best would be to try them all and monitor your transmission temps with each brand. IMHO the one that keeps the transmission the coolest is the one that eliminating the most friction thus working the best. But that is not to say that if it works the best it still may not last as long as others before it breaks down.

 

[RustyJC]

Manual transmission lube is strange stuff because it has to meet so many requirements. The high unit loading and scuffing action of the gearteeth may or may not require an EP (extreme pressure) additive. At the same time, if the lube is too "slick" (i. e. , has excessive lubricity), the function of the synchronizer balk rings may be hampered and you'll tend to get light grinding on each shift. Therefore, as we see with the different lubrication recommendations between the NV4500 and NV5600, each transmission tends to be a unique "beast" depending on its unique design criteria.



Has anyone tried contacting ExxonMobil automotive lubricant product support in Fairfax, VA to ask about specific recommendations for our manual transmissions?



Rusty

 

[Ncostello]

Guess I'll snuff out my own thread here. The Mobil 1 site says specifically that Mobil 1 synthetic gear oil can be used in GL-5 automotive applications as well as GL-4 applications in REAR-ENDS.



It specifically says NOT to use it in TRANSMISSIONS that require motor oil, automatic trans oil, or GL-4 performance requirements.



Guess that means its out for the NV4500. Guess I should have researched a little more before posting.



Now what am I going to do?? Just kidding. I've already come up with a plan B. And I am sticking to it... and it will work.

 

[Ncostello]

Just FTY only, (after a little more research)



Citgo makes some pretty good gear oils. We use it in our fire apparatus axles, transmissions, and transfer cases.



They do have one specifically for manual transmissions requiring a GL-4 performance lube.



Its called Citgear Standard XD 75W-90 GL-4 oil. If anyones feeling brave, you could always try this. Its a non-synthetic I believe cause all their synth's are GL-5 MT-1 rated. I bet its not too expensive either. I buy their stuff by the 5 gallon pail at a local oil company.



But hey, millions of miles cant be wrong. It is very obvious there are several out there that DO work well. Its all a matter of easy availability, cost, and trust. But I wouldnt use Mobil 1 cause they flat out say do not use this stuff in GL-4 manual transmissions.

 

[TPlasek]

I would like to make one more comment about these transmissions...



The bearings in the transmissions are the same type (tapered roller) and brand (Timken) as in many other transmissions. The gears are hardened angle cut gears just like "Most" other transmissions. In this respect, in my opinion, any gear oil will work with this part of the transmission. I think anything you put in there that is gear oil (with proper oil change intervals) will work just fine. The transmission runs at very close temps to the rear end and the shearing process involved is not identical but similiar in opperation.



With this beaing said, the one difference in the NV4500 is the (funny looking) padding/clutch material, that is added (lookes like glued) to the wear surface of the synchro rings. I'm not sure what effect,IF ANY, running a different oil would have on this material. I would think the different oil would only effect shift quality,for better or worse, more so then longevity. Too late for me now, but you can buy full brass synchros, just like the old days, from www.Blumenthalmfg.com. If you ran these, I can't see what difference what kind of oil you run(with regular change intervals). I am going to run a different oil in mine. The only thing I could see going wrong would be the synchro rings which are easy to replace and relatively inexpensive. (Plus I would get the all brass ones)



The one thing I did notice in my transmission, is that with 92k on the truck, there sure was a bunch or brass, bearing, and other contaminates in my transmission. Reguardless of what brand of oil was in there and how long it is suppose to be good for, all that metal floating in there could not be good for the bearings. I think, even if the oil is good for 100k miles, without filtration, it should be changed more often.

 

[RustyJC]

Originally posted by TPlasek

The bearings in the transmissions are the same type (tapered roller) and brand (Timken) as in many other transmissions. The gears are hardened angle cut gears just like "Most" other transmissions. In this respect, in my opinion, any gear oil will work with this part of the transmission.

With all respect (absolutely no flame intended), this ignores the operating variables between transmissions. An example is tooth loading and scuffing - a function of gear contact area, torque being transferred between the gear teeth, relative surface speed between the tooth mating surfaces, etc. That's why the lubrication requirements for each transmission may or may not differ, and there's no "one size fits all" manual transmission lubricant.



JM2CW



Rusty

 

[Gary - K7GLD]

The issue of dealing with proper lubricants where, Ummmm, "different" synco clutch facing materials were used was a big issue in my '98 Camaro SS - tag on transmission and in the user manual very SPECIFICALLY declared that ONLY Dexron III lube be used - and many fellas attempting to use their favorite brand/type of "snakeoil" paid the price with malfunctioning or failed trannies!



Syncro facings made of various fibres can be EXTREMELY sensitive to different lubes, are damaged quickly by the WRONG ones, or rendered inoperative if too slick a lube is used that otherwise might be entirely adequate for the gears and bearings...



That's undoubtedly one reason for the rather narrow selection of available lubes for the NV 6-speed... And ALSO why it's a good idea to stick with what the transmission maker specifies - IF you want/expect long and trouble-free life from the transmission...

 

[Jetson]

Royal Purple makes a GL-4 gear oil that is carried by many NAPA stores. I bought some, but haven't put it in yet.

 

[dremelts]

Hey guys... check out the last issue of TDR There's a very informative article in there about fluids.

 

[KrisKringle]

Well, jeepers, this looks like a dead thread, since it is almost 9 years old. However, since I READ the manual, and all of the good posts here I found out the GL5 old is a pariah for the NV4500. Great! Of course, here in Germany, full synthetic GL4 is a 'bit' hard to find. What ended up after a bunch of Political discourse, was that 'Liquid Moly- Hochleistungs Getriebeöl GL4 SAE 75W90' is what is the 'correct' oil to use. Just changed the fluid today. I did not take off the PTO cover to see what was laying in the bottom of the case... . However, the oil came out looking 'clean', although I am sure that the DPO did not change it according to service intervals. After replacing the front wheel bearing, I noticed that now there is another 'vibe... seems like the input bearing on the trans... so it goes... . JK