Page 1 of 3 123 LastLast
Results 1 to 40 of 91
  1. #1
    RC Turnbuckle Jr. O.G.'s Avatar
    Join Date
    Nov 2010
    Location
    South of St Louis
    Posts
    5,986

    Sealed differential discussion

    I started this thread to discuss the FLM sealed differential and stop cluttering up wmckay96's thread - sorry wmckay!!

    As some of you may know, I have an FLM sealed diff on order from rc-monster, and kwitty already has one and posted some sweet pics of it on a different post. (This question could be posed to Traxxas diff's that have been sealed with the gasket mod seen on this site)

    So my main question is this: how much oil should I put in the diff to make it work as it should, which is allow slipping on corners and hooking up better coming out of the corner, and on straights.

    If I completely fill it with 20,000 wt oil, will that slip more than if I 1/3 fill it with 30,000 oil?

    Any opinions/answers??
    My Black & Blue Rally is faster than your color...

  2. #2
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,047
    You are gonna make me want to make an inch-pound gage to indicate how much resistance is built up before the wheel releases to answer this one LOL your killin me you know!

    I'll contribute with you may want much more than 20k or 30k to get enough gain, my 100k doesn't seem that tight to me at all.
    I'll say your 20k fill would give 'less' slip than your 1/3 30k additive

    Sorry too if I convoluted that post of wmckay's as that wasn't my intention it is just a hot topic for me as you might notice

    Below is an internal view of the FLM trans, gears are TRaxxas, same setup internally of the stock Traxxas unit as far as gear indexing. The FLM just offers the O ring sealed version of the Traxxas and in aluminum instead of plastic. Also note as it is difficult to see but two of the planetary gears are at the top and there are two at the bottom, these are driven off the gear that is on the output axle.
    Last edited by kwitty; 05-06-2012 at 09:00 PM.

  3. #3
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,047
    Below is what I posted in the other thread so I think it should also go hear for 'discussion' purposes if you don't mind O.G.?


    I guess as long as the gears stay in a bath of the lube it would be fine but not as full of a benefit. If not for the sealed ability of the FLM then it wouldn't be any different than the. Traxxas unit. I can't imagine enough diff action as a benefit from only the bind up created by about two teeth meshing with the lube as the friction agent. Submersing the gears would only add greatly to the resistance created on all surfaces effected by being in the diff fluid which would account for an increase in the ability to slow down blow out to the wheel that becomes unloaded..

    Problem is this is really a poor way in the first place to accomplish a bind or locking action to solve the problem. I don't know of any automotive differentials that even begin to use the 'lube' as the device that creates the locking action we are looking for.
    GM used an advanced G-rotor pump that hydraulically created a very advanced trac system but others as we know are clutch engaged (posi) or gear engaged (locking) type or totally solid as in a spool.

    So, we needed to design a diff that is frictional plate adjustable and we just need a hollow axel that we can slide an adjusting tool into to tune the amount of friction we want it still baffles me that the best we have to work with is simply by fluid or it's tackiness ability to bind gear mesh, very crude and the wrong way to go about resolving the issue..

    Maybe a unit with a central gear with an adjustable clutch on each axel independent, you could bias the bite to the tires getting the weight transfer like in your circle track racing maybe even a internal drive gear with external clutching at the output shafts..

  4. #4
    RC Turnbuckle Jr. O.G.'s Avatar
    Join Date
    Nov 2010
    Location
    South of St Louis
    Posts
    5,986
    Quote Originally Posted by kwitty View Post
    That is a sweet, sweet pic. I could look at it all day.

    I don't mind kwitty, post away!

    And yes, I want you to put a ft-lb gauge on your diff to give us the internal pressures. hahaha

    Well I ordered the FLM sealed diff but I thought it had a plastic external gear based on the pics and I recall someone on this site complaining about a chewed-up plastic gear ring on the outside.

    And when I saw the red-anodized diff you posted I was so glad I ordered FLM. I'm just sent an email to swami-rc asking who makes their sealed diff; maybe they'll answer, maybe not.
    My Black & Blue Rally is faster than your color...

  5. #5
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,047
    Well here is one more for you and simply to show the Traxxas and the FLM how very similar they are.


    Look closely on the stock Traxxas and you will see the ends of the pins (4) that the gears ride on.
    Last edited by kwitty; 05-06-2012 at 09:33 PM.

  6. #6
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,047
    Quote Originally Posted by O.G. View Post
    That is a sweet, sweet pic. I could look at it all day.

    I don't mind kwitty, post away!

    And yes, I want you to put a ft-lb gauge on your diff to give us the internal pressures. hahaha

    Well I ordered the FLM sealed diff but I thought it had a plastic external gear based on the pics and I recall someone on this site complaining about a chewed-up plastic gear ring on the outside.

    And when I saw the red-anodized diff you posted I was so glad I ordered FLM. I'm just sent an email to swami-rc asking who makes their sealed diff; maybe they'll answer, maybe not.
    On the FLM there are indexing pins that can be seen that go through the gear to lock it onto the casings so it isn't going to give under pressure!
    for those unfamiliar with the innards of there differential, there is a very small solid pin that indexes into the black gear which is the output axle gear and the other output axle gear goes on top of it and that is where the top set of planetary gears mesh into. See first pic in post for reference to this......

  7. #7
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,047
    Another thought on your question about 1/3 filling, the entire differential spins, I may have this wrong but in this case only partially filling the unit would seem to make it out of balance as that thick lube is not going to remain at the bottom, it is going to flung by force against the the inner wall of the casing and remain there like a washing machine pins the clothes to the tub.

    The diff could act like and out of balance tire inside the trans?

  8. #8
    RC Turnbuckle Jr. O.G.'s Avatar
    Join Date
    Nov 2010
    Location
    South of St Louis
    Posts
    5,986
    Quote Originally Posted by kwitty View Post
    Another thought on your question about 1/3 filling, the entire differential spins, I may have this wrong but in this case only partially filling the unit would seem to make it out of balance as that thick lube is not going to remain at the bottom, it is going to flung by force against the the inner wall of the casing and remain there like a washing machine pins the clothes to the tub.

    The diff could act like and out of balance tire inside the trans?
    If the oil was pushed to the outside of the differential wall, wouldn't it be even all the way around? Or do you think the gears would be in the way causing lumps of oil that would make the diff go out of balance.
    My Black & Blue Rally is faster than your color...

  9. #9
    RC Turnbuckle Jr. rag6's Avatar
    Join Date
    Mar 2008
    Location
    PM me if ya wanna bash at Greenwood Bashplex!
    Posts
    13,066
    I have filled my other diffs 2/3 full, and they were consistent.

    I asked around at my local outdoor track. I swear everyone running the 1/8 buggies said something different. 1 thing was apparent though. Everyone's diff worked great according to them, weather it was 5/16,2/3,3/4, or completely full.


    I was looking on this site, and found this:

    roll on down to "differential"

    http://traxxas.com/pitpass/hopup/new...ng-Setup-Guide

  10. #10
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,047
    Quote Originally Posted by rag6 View Post
    I have filled my other diffs 2/3 full, and they were consistent.

    I asked around at my local outdoor track. I swear everyone running the 1/8 buggies said something different. 1 thing was apparent though. Everyone's diff worked great according to them, weather it was 5/16,2/3,3/4, or completely full.


    I was looking on this site, and found this:

    roll on down to "differential"

    http://traxxas.com/pitpass/hopup/new...ng-Setup-Guide
    Interesting on the fill. So it sounds by this tip that 'filliing' with any lube will 'increase' the diff action. So filled with 100k may equal wetted with 300k LOL
    It still is an area of tunability that is not easy to get too and is time consuming if you do and seems to not remain constant if not attended to. We need a a better tunable diff is all there is to it.

    If you half-fill the case, then drop in the other side axle gear it probably displaces another 1/4 of the interior space so now you are 3/4 full?? LOL
    Hmmmm, the mystery continues................

  11. #11
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,047
    Ummmmmm, has anybody seen this!!! YES our wishes may be reality!!

    http://www.bigsquidrc.com/rcx-2012ne...o-line-racing/

    Last edited by kwitty; 05-09-2012 at 04:02 PM.

  12. #12
    RC Racer
    Join Date
    Aug 2011
    Posts
    119
    sweet. i have finally found a tranny that will work well in my 2wd slash racer.

  13. #13
    RC Turnbuckle Jr. rag6's Avatar
    Join Date
    Mar 2008
    Location
    PM me if ya wanna bash at Greenwood Bashplex!
    Posts
    13,066
    Its not here yet 8(

  14. #14
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,047
    Quote Originally Posted by rag6 View Post
    Its not here yet 8(
    But it exists!!

  15. #15
    RC Turnbuckle Jr. O.G.'s Avatar
    Join Date
    Nov 2010
    Location
    South of St Louis
    Posts
    5,986
    Nice find kwitty, that thing looks great and I have to have one. Unfortunately I'm usually a 'late adopter' so it may be a while before I buy it to let proline work out the flaws.

    I wonder what the projected price is? And if it fits the Pede and Slash it should fit the Rusty.
    My Black & Blue Rally is faster than your color...

  16. #16
    RC Turnbuckle Jr. rag6's Avatar
    Join Date
    Mar 2008
    Location
    PM me if ya wanna bash at Greenwood Bashplex!
    Posts
    13,066
    There is an entire thread about this in the pede forum^^^

  17. #17
    RC Qualifier
    Join Date
    Dec 2011
    Location
    Vancouver, B.C. Canada
    Posts
    255
    will 100k fluid in the flm unit act as totally locked or will it still jave some give? im currently running i belive 30k and it is hardly loocked at all
    Slash 2wd Vxl, ERBE; Crash N Learn

  18. #18
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,047
    My thought, unless its locked its not. The diff lube in the case will likely warm and thin a bit. If there is air in there then you are likely to have a mix of oil with air which will reduce the viscosity.
    If there were a way to match diff lube to diff grease then it might be easier to figure but since we all have wanted something thicker or with more diff action lock up then most all the greases offered I think you might benefit from the 100k and may go higher from there............
    For as thick as that stuff pours, I mean ooozes you will be surprised still how easy it feels on the diff action......just my opinion
    Last edited by kwitty; 05-14-2012 at 03:40 PM.

  19. #19
    RC Qualifier
    Join Date
    Dec 2011
    Location
    Vancouver, B.C. Canada
    Posts
    255
    ok i know on that hop ups page O.G. was talking about the guy said a little bit of 300k was equel to a full diff of 30k and soo on. so i fully fill my diffs and change the oil quite often they should have a pretty loocked feeling?
    Slash 2wd Vxl, ERBE; Crash N Learn

  20. #20
    RC Competitor
    Join Date
    Dec 2011
    Posts
    52
    Ok so when is the release date of the proline transmission anybody heard yet I have been trying to find it to no avail.

  21. #21
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,047
    Quote Originally Posted by scooter2998 View Post
    Ok so when is the release date of the proline transmission anybody heard yet I have been trying to find it to no avail.
    I had a few email exchanges with PL on this trans, they are running them now to work out any final glitches before release. That is the best I got from them.

  22. #22
    RC Qualifier
    Join Date
    Dec 2011
    Location
    Vancouver, B.C. Canada
    Posts
    255
    uuggghhh suspense is killing me
    Slash 2wd Vxl, ERBE; Crash N Learn

  23. #23
    RC Turnbuckle Jr. O.G.'s Avatar
    Join Date
    Nov 2010
    Location
    South of St Louis
    Posts
    5,986
    I was hoping my FLM diff would have arrived by now.

    I exchanged emails with the swami guy and his diff supplier is not FLM, so it must be a different design. He also said his might leak with lighter weight oil.



    Sent from the cockpit of my Jeep Wrangler
    My Black & Blue Rally is faster than your color...

  24. #24
    RC Qualifier
    Join Date
    Dec 2011
    Location
    Vancouver, B.C. Canada
    Posts
    255
    that sucks. it sounds like a waste then cause the flm diff is cheaper and has a no leak gaurente
    Slash 2wd Vxl, ERBE; Crash N Learn

  25. #25
    RC Turnbuckle Jr. O.G.'s Avatar
    Join Date
    Nov 2010
    Location
    South of St Louis
    Posts
    5,986
    I began racing my 2wd slash in the novice class at my local track and I'm really looking forward to running a sealed diff. RC-Monster sent me an email April 29th saying they received payment but still no diff. I sent another email today asking for an update.

    I'm tempted to buy one from Swami to see how fast it can get here so I can drop it in and GO!!
    My Black & Blue Rally is faster than your color...

  26. #26
    RC Turnbuckle Jr. O.G.'s Avatar
    Join Date
    Nov 2010
    Location
    South of St Louis
    Posts
    5,986
    Quote Originally Posted by kwitty View Post
    My thought, unless its locked its not. The diff lube in the case will likely warm and thin a bit. If there is air in there then you are likely to have a mix of oil with air which will reduce the viscosity.
    If there were a way to match diff lube to diff grease then it might be easier to figure but since we all have wanted something thicker or with more diff action lock up then most all the greases offered I think you might benefit from the 100k and may go higher from there............
    For as thick as that stuff pours, I mean ooozes you will be surprised still how easy it feels on the diff action......just my opinion
    Does anyone know how hot a diff gets after 5 or 10 minutes of running time? I guess that needs to be taken into consideration as well.
    My Black & Blue Rally is faster than your color...

  27. #27
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,047
    Quote Originally Posted by O.G. View Post
    I began racing my 2wd slash in the novice class at my local track and I'm really looking forward to running a sealed diff. RC-Monster sent me an email April 29th saying they received payment but still no diff. I sent another email today asking for an update.

    I'm tempted to buy one from Swami to see how fast it can get here so I can drop it in and GO!!
    Check out SPC racing in PA, they stock FLM, Jakey is here on the forum often is most helpful!
    Also shows in stock at Stormer Hobbies!
    Get with it man LOL

  28. #28
    RC Competitor
    Join Date
    Dec 2011
    Posts
    52
    Thanks Kwitty I hope they will be here soon! So far all of th eproduct I've bought from ProLine have been top notch.

  29. #29
    RC Turnbuckle Jr. O.G.'s Avatar
    Join Date
    Nov 2010
    Location
    South of St Louis
    Posts
    5,986
    I got a response today saying they drop ship directly from FLM so RC-Monster doesn't actually stock them so I have to wait.
    My Black & Blue Rally is faster than your color...

  30. #30
    RC Qualifier
    Join Date
    Dec 2011
    Location
    Vancouver, B.C. Canada
    Posts
    255
    i am still waaiting on my flm diff too... talk about slow. the owner of my Lhs told me it would be about 2 weeks but could be as long as 6. he said Flm stuff is a hot product and their facility isnt exactly the fastest. its been about 2.5weeks now and still nothing.
    O.G. do you run the crazy horse diff fluid? if so is it as good as it's said too be, anyone else running it?
    Slash 2wd Vxl, ERBE; Crash N Learn

  31. #31
    RC Competitor
    Join Date
    Dec 2011
    Posts
    52
    Quote Originally Posted by kwitty View Post
    My thought, unless its locked its not. The diff lube in the case will likely warm and thin a bit. If there is air in there then you are likely to have a mix of oil with air which will reduce the viscosity.
    If there were a way to match diff lube to diff grease then it might be easier to figure but since we all have wanted something thicker or with more diff action lock up then most all the greases offered I think you might benefit from the 100k and may go higher from there............
    For as thick as that stuff pours, I mean ooozes you will be surprised still how easy it feels on the diff action......just my opinion
    You are right to a cretain extent greases and oils will thin/viscosity change with temp but not air. Aeration of flds is something different it prevents more of the lubrication abilities. Here is an example that maybe easier to understand. In a full size car the rear diff is only filled abt. halfway well the bearings and gears get oiled by "slpash" creating a lot of aeration. Kinda like putting a blender on egg whites of whipping cream aerating them. So they put additives/bonding agents in oils to help prevent this. What it does it create a small space where there is no fld/grease less lubricating ability and not doing its job.

  32. #32
    RC Enthusiast
    Join Date
    Apr 2012
    Posts
    20
    Can I Add this thicker weight oil to my Stock 2wd slash gear box or is this just for aftermarket boxes? I was looking for a fill plug with no luck

  33. #33
    RC Turnbuckle Jr. O.G.'s Avatar
    Join Date
    Nov 2010
    Location
    South of St Louis
    Posts
    5,986
    Quote Originally Posted by dshaff24 View Post
    Can I Add this thicker weight oil to my Stock 2wd slash gear box or is this just for aftermarket boxes? I was looking for a fill plug with no luck
    Yes you can add thicker oil or grease to the differential on the 2wd slash/rustler/stampede (all three are the same) by opening the transmission case to remove the differential then adding thicker material. The stock differential isn't made to be leak proof which is why thin oil will leak out quickly while thick grease like lithium based wheel bearing grease will stay inside the diff longer.

    Opening the diff sounds more complicated than it is, but necessary if you want to make a fluid change.

    Take a look at the pictures in post #5 that Kwitty made and you'll see the transmission internals. The thicker oil/grease goes inside the differential which is the large white thing.

    Sent from the cockpit of my Jeep Wrangler
    Last edited by O.G.; 05-16-2012 at 01:10 AM.
    My Black & Blue Rally is faster than your color...

  34. #34
    RC Turnbuckle Jr. O.G.'s Avatar
    Join Date
    Nov 2010
    Location
    South of St Louis
    Posts
    5,986
    Quote Originally Posted by wmckay96 View Post
    i am still waaiting on my flm diff too... talk about slow. the owner of my Lhs told me it would be about 2 weeks but could be as long as 6. he said Flm stuff is a hot product and their facility isnt exactly the fastest. its been about 2.5weeks now and still nothing.
    O.G. do you run the crazy horse diff fluid? if so is it as good as it's said too be, anyone else running it?
    In my bashers I like to run Bad Horsie differential grease which is some thick stuff and is applied with a spoon or tongue depresser.



    But don't put that stuff in your shiny new FLM diff because you'll never get it out without a lot of work and a complete replacement of the internal gears. I tried to clean it out of a traxxas diff once and didn't work. BUT, it's great stuff for the stocker differential to get a limited slip feel.
    My Black & Blue Rally is faster than your color...

  35. #35
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,047
    I just got my first tub of that goo, it's not cheap at $10 for 1/4 ounce! That is over $5000 a gallon woweeee!!
    However it does seem ultra sticky, not a fluid for submersion but an application for contact surfaces of meshing. Will give it a try in my gransons Slash and my stocker most likely next.

  36. #36
    RC Qualifier
    Join Date
    Dec 2011
    Location
    Vancouver, B.C. Canada
    Posts
    255
    thanks og in my flm im going to be putting 30k and going from there... but i am currently working on having a spare box with the stock diff is the bad horsie thick like grease so that it wont leak out of the stock Diff?
    Slash 2wd Vxl, ERBE; Crash N Learn

  37. #37
    RC Turnbuckle Jr. O.G.'s Avatar
    Join Date
    Nov 2010
    Location
    South of St Louis
    Posts
    5,986
    Quote Originally Posted by wmckay96 View Post
    thanks og in my flm im going to be putting 30k and going from there... but i am currently working on having a spare box with the stock diff is the bad horsie thick like grease so that it wont leak out of the stock Diff?
    Yes it's super-thick, similar to chapstik only sticky so if you touch it, the stuff will stretch between your fingers and get all over the place. I just opened up my transmission case and the Bad Horsie grease is still inside.

    When you add the grease to your diff, remember to take into consideration the space the screws and recessed lid take up inside the diff, otherwise it will be overfull and you'll waste some when it squished out as you push down the diff cover. You'll like the feel of it the first time you drive.
    My Black & Blue Rally is faster than your color...

  38. #38
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,047
    I just goooped up a stock diff with the Bad Horsie elastic-like grease. I simply coated all gears on the teeth. It doesn't appear this stuff is designed to flow but to provide super adhesion to surfaces. After assembly and comparing it against my assembled FLM filled with 100k diff oil, I believe the Bad Horsie has more resistance.
    I have an idea on devising a testing system to measure the amount of force it takes before 'break away' of the lock up resistance provided.................stay tuned

  39. #39
    RC Turnbuckle Jr. O.G.'s Avatar
    Join Date
    Nov 2010
    Location
    South of St Louis
    Posts
    5,986
    Quote Originally Posted by kwitty View Post
    I just goooped up a stock diff with the Bad Horsie elastic-like grease. I simply coated all gears on the teeth. It doesn't appear this stuff is designed to flow but to provide super adhesion to surfaces. After assembly and comparing it against my assembled FLM filled with 100k diff oil, I believe the Bad Horsie has more resistance.
    I have an idea on devising a testing system to measure the amount of force it takes before 'break away' of the lock up resistance provided.................stay tuned
    I can't wait for your research Dr. Kwitty. lol

    How do you like the new diff setup? I've always filled my diffs when I did the bad Horsie Mod.
    My Black & Blue Rally is faster than your color...

  40. #40
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,047
    Quote Originally Posted by O.G. View Post
    I can't wait for your research Dr. Kwitty. lol

    How do you like the new diff setup? I've always filled my diffs when I did the bad Horsie Mod.
    Well at least I might be able to offer a reference point of comparison to share
    That stuff reminds me of a slightly thinned out Silly Putty!
    Now if I can just find a good place and time to drive these dang things I am tinkering with LOL We'll see how my grandsons diff works out soon, he is anxious for me to get him back up and running, just waiting on bearing kit for the Velineon and off he goes...........

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •