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Castrol Syntorq Replacement

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Howdy gents,

Has anyone changed out the Castrol Syntorq 90W oil in their NV4500 gearbox and used another oil when refilling? You always hear the scare tactics from New Venture and Castrol and I just wanted to know if they were true or if folks have had good luck with Amsoil, Redline or other better, cheaper oils.

Thanks for the help,

Steffan Marley
 
This subject has been beaten to death so badly, I don't know if anyone will post. . LOL



NV says castrol, others have had good luck with a wide variety of oils...



I'm not telling what i use. . it costs too much and I'm sad to say i bought it... :)



But my warranty said to use "*&^%$*(^%" and I did...
 
Amsoil Series 2000 75W-90.



It works, better than the factory lube from my exprience.



Check out my sig, it will give you an idea about the battles that have been fought on here about this!LOL
 
SynTorq is a great lubricant for the transmission and has a good price from Standard Transmission in Ft Worth. 60 bucks a gallon to your front door.

My thoughts are to change the lube faster than any 100,00 miles than the factory asks. I go about 25K and dump it.

Castrol makes lubricants for all kinds of specialty applications. The NV4500 is just one of hundreds. After a long search on material safety data sheet web sites I have found hundreds of specialty lubes including special applications oils and lubes for the militaries machine guns, tanks, etc.



The price of these lubes is high because the application is very limited. Not too many gallons are produced to speak of when you think of the daily sales of the lubricants for our transmissions. Heck the factory claims it is a lifetime fill. Castrol cant make thousands and thousands of gallons of the oil to get the price break any better. Hence the price is somewhat steep.



There are several reasons to use the Castrol oil in the NV4500. Some are obvious and easy to figure out and some are not. Proprietary information about the SynTorq and why it works so well is not out there for everyone to see and when people are told the price they jump out of their skin.



Syntorq's ability to keep the heat down and not attack the soft metals in the transmission is in the proprietary formulation.

A formulation that is expensive. Since the Syntorq is only used in the NV4500 transmission the oil is not sold in quantities to support the Wal-Mart deals everyone looks for.



Don~
 
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""Syntorq's ability to keep the heat down and not attack the soft metals in the transmission is in the proprietary formulation.

A formulation that is expensive. ""





Proprietary formulation, Is exactly why Amsoil is safe to use in this transmission where other GL-5s are not.



I have also noticed in industrial lubricants, the big companies like to put a price spin on "special formulas".





Gene
 
Luckily we are not talking about price gouging with the Syntorq.

Since the oil is only used in and specified for the NV4500 transmission and the sales are limited so the bulk discount is not there for the Syntorq to drop in price.

Most exclusive and limited production products do have a higher price. Supply and demand still drives the market price for nearly all consumable products we buy.



Since I dont have the price of dealer Amsoil I did the internet price comparison below from Amsoils website.



Amsoil:

$9. 20 a quart x 4 quarts = 36. 80 plus roughly 15 bucks to ship it to your door = 51. 80 plus tax because Amsoil charges sales tax on internet sales. So close to 54. 00 bucks or so.



Castrol Syntorq: 60 dollars to your door



So you save about 5 to 6 bucks to go with Amsoil. Where is the big price break and how can 5 dollars be considered a "price spin" from Castrol?





Don~
 
I recently reported dyno testing for drag from different NV4500 lubes. The Castrol was best, flat out. Torco RTF was very close, and has the GL6 additive rating for those worried about gear wear. If the lube doesn't get hot, it is easier on the brass synchros. The Castrol and Torco were slow to heat up. It took several full power passes on the dyno to get them to 140 deg. Another popular lube came up to temperature with just one pass. That suggests to me that friction was higher with it, and its higher drag figures (taken in neutral gear, coasting down from 110 mph) supported that guess.



However, to get another kind of answer I asked the possibly most learned pertroleum/lubricant engineer (degrees, certifications, etc. ), Kevin Dinwiddie. He told me to use Castrol. He sells LE and could have recommended their LE607 (90 wt) or LE606 (80 wt?). Since he took his company out of the controversy, and therefore "doesn't have a dog in this fight" I felt his advice was well meant, and not self serving in any way.
 
Well Don, if you want to compare the cheapest price on Castrol, you should find the cheapest place to buy Amsoil also, not the most expensive way-internet sales. Wouldn't that be fair??



Doesn't the Castrol have shipping also? Not everyone can drive to Texas to save shipping costs. And $15 is more than twice what shipping would cost.



Joe, I can't believe you keep playing with those dyno things.

The real test is out on the road, loaded,uphill, pulling away!



Our local shop specializes in Dodge transmission rebuilds, and they do not refill with Castrol, anymore, for good reason--they wanted to keep their customers on the road, not in the shop. They cater to hot shotters and Hi-Performance trucks.



Stockers not towing the Castrol will work fine, I'm sure.





But hey, if you guys are set on factory specs, best just leave that Castrol in there forever, don't change it, because Mother Mopar calls it a "LIFETIME LUBE"



Whos lifetime, we ain't sure. :D
 
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Like I said the Syntorq from Standard Trans is to your front door for 60 bucks. Its cheaper if you go to them in person.

Anyone in the country can get it for 60 bucks shipped.

I did not know the dealer cost of Amsoil so I could not put it up. The Syntorq price was for anyone at anytime w/shipping.

The comparison was to show that the Syntorq is not much more money than the "alternatives" are. Not a jab at all to Amsoil. It is cheaper than Castrol afterall, not more.





Another part of the puzzle I can tell you about Castrol Syntorq is the TAN numbers and how far out of spec the "alternatives" are. Syntorq starts out with a TAN of 0. 6. This is very low and we know the reason for this is the soft metals of the transmission. As TAN (Total Acid Number) increases, the ability of the oil to attack soft metals goes up. Most "alternatives" start out with a TAN number of over 2 and the last "alternative" I tested came back with a TAN of 3. 2. Very high and way out of the specs from New Venture for the NV4500. NV wanted the TAN number to never exceed 1. 2. With many lubes exceeding this out of the bottle the choice is clear.

TAN increases rapidly with water from natural condensation, backing your boat in the lake, etc. Coupled with heat from towing that boat or trailer can increase the TAN number and the aggressive additives in the "alternatives" can begin to chew away at those expensive syncros. Im fully aware that some "alternatives" have a buffering packing to help combat the high TAN numbers, but I did not feel comfortable with the chemistry many of the "alternatives" used.



Im not saying that the "alternatives" are not high quality lubricants. Far from it. My argument is based on the Syntorq's heat controlling ability and the formulation of the lubricant was developed and specified by the transmission builder just for the NV4500. No other gear box, axle, etc uses this oil.



I still agree with those who say we should change the oil in our transmissions faster than DC recommnends. I go about 25K. 60 bucks once a year or so and Im set with the proper lubricant.



Don~
 
Gear Lube for the 5 speed

Guys, I've tried both Amsoil and Syntorque. The OEM fill seems to make the trans shift a little smoother. JMO:D :D :D
 
Gotcha on the shipping, that means shipping should be the same between the two then, not $15 for the Amsoil.



The facts remain, that Standard's hottest seller is the NV 4500.

They dump the factory lube back in. Go figure.



Amsoil has been used in these trannys since they came out.

All we have heard is the nervous nellies scared out of their mind from that little sticker, and what the "EXPERTS" say could happen, shoulda, coulda, yea we know.



Amsoil is not shy about telling people they don't have a product for certain applications. In this case, however, they stand behind their lube in this transmission.



That facts remain, we are using this lube,(among others) it is working, better than factory in the extreme conditions of hot shotting from what we have seen, no oil related failures to date.



I noticed no difference in shifting between them. Many claim the Amsoil shifts better.













.
 
Like I said the "alternatives" are cheaper to buy than the Syntorq. But remember the market share for an exclusive product like Syntorq is small. It only goes in the NV4500. Taking the 60 dollar per gallon price of Syntorq, the number of oil changes, and number of NV4500 transmissions out there and applying the same supply and demand functions to the "alternatives" makes the others about a 3 dollar a gallon oil. Not that the "alternative" is crappy oil, but supply and demand drives the market price of products. Syntorq's price is directly affected by this function. The "alternative" oils should be much cheaper in price using the above.

After speaking with the guys at Standard Transmission about the NV4500 and it being so popular they feel the reason they fail so often is overloading. Many hot-shot trucks run more weight than the transmision was designed for over long hours on the road. Since Standard rebuilts more transmissions of this type than any other rebuiler out there they see everything and have seen everything long before other shops ever started rebuilding them. Standard tried "alternative" lubricants and keep coming back to the Syntorq after the failure rates went up. Small shops in the outskirts of the market with a small amount of data cant make as good of a comparison as the guys who rebuild hundreds more per year.





Another informative fact is that Syntorq has the rheological properties to climb the gears and lubricate them properly while other oils are not as close to the Syntorq rheologically. Not all 75/90 weight oils have the same viscosity as Syntorq. Viscosity has a broad range between 75 and 90 weight and the two are pretty far apart in actual numbers. This can help explain Joes heat testing and the fact that some of the "alternatives" got hot faster.

The splash lubed NV4500 needs the Syntorq that was developed for it.

Searching for an alternative in this case has not lead us closer to a better than product we already had. "Alternative" NV4500 lubricants are no better than the "alternative" lifestyles that some others are trying to live.





Don~
 
QUOTE]The facts remain, that Standard's hottest seller is the NV 4500. [/QUOTE]









Sled puller,

When your one of the best at fixing the NV4500 of course you are

going to rebuild alot of them. That was really an unfair statement.



I bought my truck with 11700 miles on it and the syncros were out in 3rd and 4th. I had a local shop replace them. It worked fine for the next 20000 miles and now the syncros are out in 3rd again.

Guess what kind of lube I used "amsoil"

I now have an a reason to use castrol

This is just what happened to me.

Dennis









[
 
--Joe, I can't believe you keep playing with those dyno things.

The real test is out on the road, loaded,uphill, pulling away!--



Dyno testing is reproducible and gives good data. The scope and limitations of the experiment and the data need to be evaluated. Knowledge of experimental design and data interpretation help. Twenty or thirty years of conducting scientific experiments helps. Driving a pole truck doesn't give the ability to do this. Experience selling oil doesn't do it, either. Kevin Dinwiddie has education and training, along with certifications, so he is qualified to speak. I value his judgments, and he tries not to "sell" his oil. He presents test results that show how his stuff performs. In the case of the NV4500, he honestly states that LE607 (and other lubes in the correct viscosity and additive range) would work, but advises us to stay with the Castrol because it is the best lube for the transmission.



It's natural to be suspicious of tests you can't understand. Yes, pulling a load is the ultimate test, but it is very difficult to reproduce experimental conditions. It is also difficult to accumulate accurate data. You need to monitor transmission temperature vs. load vs. time. Fuel mileage would be an indicator of drag, but it is too imprecise as there are too many other variables. It is also difficult to see short-term the effects of long-term use of other lubes, because temperature, humidity, and other variables are difficult to control. Even when failure occurs, there are so many contributors that it is difficult to assign the "blame". Hence, scientific testing is used to isolate variables and test them.



The limited tests I performed showed that only Torco RTF, of the lubes I had available for testing, came close to Castrol Syntorq in horsepower drag. Drag or friction is one of the properties that relates to the performance of Syntorq and other lubes in the NV4500. Transmission temperature is another. On-the-road testing showed that transmission lube temperature was similar to that of Syntorq. Shift quality was good. However, what about high temperatures and humidity, conditions that contribute to breakdown of the lubricant? For my use, in low humidity areas, RTF would work. I expect that some other lubes would, too. Under extreme conditions of load, temperature, and humidity, I don't know. As Kevin said, the GL6 additives of the RTF would probably be a bit better for gear tooth protection. Syntorq would be better for the synchronizers.



There are a number of honest, polite oil salesmen on this forum. Many of them use and sell Amsoil. That is fine with me. Each customer should pick the lubricants he/she wants to use.
 
The syncros are made of brass and can be attacked by the aggressive additives in the "alternative" oils that are marketed to consumers as the superior lube for the NV4500.

Many concerned lubrication engineers avoid this pitfall and go with and recommend the use of Castrol.

Another problem is... the warranty that the "alternatives" give you to cover such damage is null and void if you modified the truck or ever pulled more weight than the transmission was designed for. This covers a large portion of the TDR members.

Syncros are not the only soft metal pieces used in the design either. Any soft metal can be subject to being slowly being washed away by the additives in the "alternative" oil.

Some of the particles that are eroding cant always be seen with the run of the mill oil analysis because the particles are too large to show up. Ferrography would help in this case to show what the 20 dollar oil tests cant. By the time guys spend lots of dough to see if the "alternative" is working properly in their application and use it is easier and cheaper to just use the Syntorq and know the soft metals are not an issue. Ultra low TAN numbers in the Syntorq make it a better choice for soft metal syncroed trannies.



Don~
 
Hey Don,,Are ya speaking in forked tongue here or what??... ...

" Another problem is... the warranty that the "alternatives" give you to cover such damage is null and void if you modified the truck or ever pulled more weight than the transmission was designed for. This covers a large portion of the TDR members"

So what in the blue blazes are you telling the membership here??,,Its not warranty approved to use any other gear oil,EXCEPT Castrol,in a highly modified truck???,,The alternatives(LE,Torco,Amsoil,Red Line,etc,etc)will not warranty our transmission failures due to excessive weight or power,but,Castrol will??,,We've already been thru this warranty white knight stuff with you so why or when are you going to post facts and not use scare tactics anymore,,One can not believe that even with the post in front of you,you post such a statement,,Gotta wonder what Castrol would think of you telling everyone that by using their product,even in a modified truck or overloaded truck,that they would warranty the failures just for using it..... Man you are too much..... Andy
 
The "no warranty" quote was for Dennis on the last page. His syncros have gone out after 20K and it very well could be from the use of Amsoil. I simply let him and others know that if the truck is modified the warranty from Amsoil is history and DC would be hard pressed to give any coverage either. The reason I did this was because I was told that if the transmission failed from the use of Amsoil that Amsoil would cover the cost of repair.

I have no doubt they would cover it if the oil was proven to be the problem and in a stock vehicle, but I was NOT told that if the truck was modified it would NOT be covered. I was mearly trying to save him the hassle of trying to get coverage from Amsoil and potentially be denied.



So, in trying to keep the topic factual and informative and not slam a product I simply pointed out his inability to get it covered through Amsoil.

I just felt it simply did not need to be repeated to others that modifications can lead to expensive repair bills out of pocket because the majority of the members are all too aware that "they are their own warranty stations".

In my experience with new vehicles and warranty coverage in the past that I modified, dealers were always willing to overlook mild power enhancements or infractions. Using an unapproved lubricant is hard to explain away to a service writer or zone manager who has little to no experience with "alternatives"



Im not sure how you interpreted what I have written or how you came about your conclusion, but you are incorrect in your assumption if I have read and decrypted your post correctly.



Don~
 
Originally posted by Dbonzi

I bought my truck with 11700 miles on it and the syncros were out in 3rd and 4th. I had a local shop replace them. It worked fine for the next 20000 miles and now the syncros are out in 3rd again.

Guess what kind of lube I used "amsoil"

I now have an a reason to use castrol

This is just what happened to me.

Dennis

[





Guess what we have in common!??????



My third gear synchro went out under 30,000 also. Except Castrol was in the transmission!!



Much to Joes dismay, I did NOT blame the Castrol. I then had a REAL reason to use Amsoil, not just saving $15 per qt, (stealer only, at that time)



I had the transmission rebuilt properly, and added the Amsoil. Well, it has over 100,000 on it now, no more synchro problems.



These trannys fail every day with Castrol, how come nobody even considers posting that the Castrol ruined them??



The double standards on this site are pathetic. :rolleyes:



Gene
 
For me it's a no brainer, just use the stuff they say to use on the side of the transmission, Syntorq. It's not like you're changing fluid every 5k, price should be no objective.
 
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