Engine/Transmission (1998.5 - 2002) Fibrous Syncro??

[Diesel Nut]

I just spoke with a NVG service location about the oil to run in my 6 speed. I was having problems getting it into 1st and reverse with 27K miles on it. I told him that it has redline MTL in it and he said right off that that was a bad idea. Apparently the syncros in this trans have a fibrous material built into them and according to this person, any other oil will eat up that fibrous material. I guess the Mopar oil recomended for the trans is $90 a gallon at the dealer, and he can get it to me for around $50. Anyone know anything about this? Seems kinda funny to me that you can only use one type of oil no matter what, ya know?

 

[HeberRam]

Diesel Nut... I don't want to sound like a know it all, however, Redline MTL, Amsoil, or any other petroleum based motor oil will not hurt those syncros. In addition, the so call "mopar" oil is simplely a texaco brand oil. In fact the 2003 Nv5600 trans, which is the same trans as yours, does not specify that oil. I run Redline MTL in my 2001 6-sp, and in fact it made my trans perform better then ever. I also added prolong trans friction modifier and got even better results. I don't know when you put the Redline in, and if you put it in and now have a problem, or have had it in for a long time and just developed a problem? Two things come to mind, #1. there was a TSB regarding this problem and a warranty correction, #2. It could be a symtom of a bad pilot bearing in your clutch.

 

[MikeBeggy]

I'd like to share my first hand experience, not just my thoughts based on what others may say. I first changed my oil at 12k or so to remove the normal breakin 'dust'. I search the forums and decided that cost of oil was insignificant so I went with the best. I used an Amsoil product the was for my aplication. To make a very long story shorter. over a period of about 80k miles and oil changes at 25 to 30k, the fiber syncros indeed deteriorated to such a level that my trans was developing grinding in most gears. I changed back to the recommended Castrol and regained shifting smoothness to about 75%. I decided to install the fully splined shaft and see what the syncros looked like. I also discovered that several of the major trans overhaulers would not warranty thier units if other than Castrol was used. I am now about 60k miles on the new syncros and all is perfect. The people that design and sell these units ought to know what is best. I found out the hard way that in my case, they certainly did.

 

[Diesel Nut]

Put in oil (redline everywhere but motor) around 3,000 miles. Am at 27,000+ now. So, Redline has about 24,000 pretty hard miles on it. Lots of towing, lots of highway, lots of hotrodding through town. Did I mention I've only had the truck 11 months? She turns 1 year May 31st.



HerberRam - Have you had problems with you 1st gear/reverse shifting? It's been doing it on and off for about 10k miles and not as much when warmed up.

 

[HeberRam]

DN... . From the very start , I always had hard shifting, and even at 10,000 miles the shifting did not get any better as others claim. Never had an "extreme" problem in 1st or reverse. A friend of mine Peter of SouthBend Clutches, suggested I try using Redline MTL, along with prolong to see if this might help, as others (6-sp) owners, were complaining to Peter, that perhaps his clutches were causing the problem. Well, I tried his recommendation, and instantly the transmission came to life, after 32,000 miles of frustration!!! There was also, a Dodge Tech. Bulletin, ( I'll try to find it for you) regarding a fix for customers experiencing severe problems. The dodge manual for our trucks, basically, says maintenance free!!! No need to change, just top off!!!

Use only Texaco @#@@$. That product is a simple Texaco brand of 5w-30w motor oil, re-branded for Mopar for exclusive in house sales. Despite what "others" say, I do have some fuel & Oil experience for I worked for Chevron for 20 yrs. , helped develop and Market Delo 400 , as a lube engineer. Common sense should have told me there is no such thing as a maintenance free oil! Anyway, I believe the 6-sp trannies have such tight tolerances, they need to be kept cool as possible, have high lubricating property oils, and increased friction modifiers. Whether, Amsoil, Redline, Mopar "texaco" or whatever works for you, use it. Unless you use something with high detergent properties ie. , and not specific or specified for manual transmissions, you will not hurt the transmission through normal use. However, saying that, abuse, drag racing, truck pulling, dynoing, miss- shifting, heavy load pulling " will'' have an effect on reliability, wear and performance. Proper clutch and related parts of the clutch can also effect performance and wear. I would suggest, you change your transmission fluid and let us know the results? The other possibility, and you can contact Peter at South Bend Clutches and relate the symptom's, is worn out clutch parts.



Steve

 

[rubberneck]

FWIW, I have tried the amsoil 5w30 and the redline mtl. The amsoil worked fine, the MTL made my truck shift badly. Very notchy and even a little grind when cold. The colder outside the worse. I am now running the factory lube and that is what will continue to run in my box. my . 02

 

[HeberRam]

rubberneck, just curious, can you tell me at what mileage you used the Amsoil? Same with the Redline? And, again, if the Amsoil worked fine before, why did you switch back to the factory oil? Like you , myself and others with 6-sp's, we seem to all have different results with transmission fluids? I'm trying to pin this thing down, and any information would be helpful. Oh, any clutch changes or mods done to your truck during these different transmission fluid changes...



Thanks, Stevel