EATON FULLER 13 DOUBLE OVERDRIVE TRANSMISSION

Hi, first off. Through out this im gonna give as much detail and be specific as i can to give you the best idea of what im doing and tryin to learn. I Would love to hear anyone's knowledge and advice.. Sorry in advance if it turns out long...

I have a 93' Kenworth W900L with a 307" wheelbase. 500HP 3406B model CAT. With an eaton fuller 13 speed double overdrive transmission. Either 3:55 or 3:36 rears I think they are :36's I forget to check every time im down there servicing. It's the first D.O. transmission that ive owned... I've had nothing but 13's and 18's.. Since its not a regular 'H' pattern 13.. and 13th gear is up against the dash. I'd like for anyone who could tell me the goods and bads on this Transmission and the does and don'ts on this particular transmission that I may not know or not be aware of, it would be greatly appreciated.. i want to know everything that i can about it. part of the tag on the transmission is ripped off but the number that's on it says OO14613RB. So I'm assuming the RT is ripped off so it's an RTOO146RB. Correct me if im wrong .. I have found little to absolutely no info about it on any site whatsoever It's a 100mph truck easily. Only done it bobtailing.. pulling anything I don't touch 12 and 13 gear.. usually doing 65 to 70 adn 10 barely find myself in 11th even.. When im loaded ive always kept my rpms 1700-1800. Emtpy between 1600-1700, usually 1700 empty. I pull hopper trailer grossing around 94,000 give or take in the state of North Dakota mostly and the some of the midwestern state's. Dont see mountains often ... one of my questions is.. when I start off on my bottom rack of gears. In low which I call 1st gear, it's a little bit of a pain to get into 2nd. But after that other gears are fine.. after splitting the range selector up and going through your top rack. Going into 6th.. if I leave it in the gear and split to 7th it kinda jumps or hops, not a smooth transaction. Not completely horrible but i dont like it. other gears don't do it quite as bad or sometimes not at all. So with this Transmission on the count of 6th splitting into 7th being the worst of them. Ive also pulled it out of gear, split it then put it back in. Creating a habit of doing it to all of them beings it seems to be easier and smoother on the tranny.. If I go from 10 to 11 I split while it's in gear and that seems to be the best one that don't hop or jump. Goes smooth likes it's supposed to. While down shifting and this is one of my main questions. When in 6th going flipping range selector down to go in bottom rack.. I pull it out, flip it and go into 5. But alot of times it'll grind for a few Seconds in the process. If I pull it out wait few seconds before flipping it. Then flip it it does fine.. what is causing that issue?? ...... Also I've always ran 50 Weight synthetic oil with one gallon of lucas on my older transmissions. I change oil regularly like a person should and have never had any issues. Since the serial number has a 6 in in it 14613. Ive heard anything with 6 or below ive heard of alot of people running thicker oil, such as 80-90 oil. Kinda worries me in transmission but then again dont see what would be wrong either. I run it in my rear ends. Would like people's thoughts on that as well. I float shift my gears and always will i dont double clutch, but if there's anything that seems like I'm doing wrong other than that cause that i already people are gonna comment about that im sure. With this particular transmission I'd like to what could be damaging it without me knowing it with something im doing... I would like you to be completely honest with me and tell me everything I need to know about this transmission and also whats the difference between RTO and RTOO on the serial number and what does the RB at the end stand for?? I want to know every single detail someone can give.. what I could be doing better to improving the life of it, on the account of how I drive it, where im driving it and what im hauling and also the info that's causing the small issues I'm having with that I listed.. thank you for reading if you've made it this far tried to explain everything the best I could.

 

It has done since I bought it.. when I bought it. The older guy I got it from he said he's ran lucas in all his trucks never had a problem and had 3 gallons in this one along with 1 in each rear.. I thought 3 in the transmission was a little much especially how cold it was gonna be over here. Changed it and the old local guy I get advice from said to put 40 weight in which I ended up doing and changing it for the first time. And by the looks of the oil it didn't like its been changed ever it was bad. So I've ran this for about 60,000 and gonna drop it because I wanted to rinse it out from how bad oil was before. put 50 instead from what I've read and since summer is here basically put gallon of lucas in it now.

 

Yeah the syncronizers was my first concern. Had an old one that started doing it all the time no matter what.. so was hoping that wasn't the problem with this one since it only does it maybe once a day usually

 

OK thank you for letting me know that!