How to change differential oil?

Mar 29, 2011
1,162
333
Mountain Home, AR
Name
Mike
Has anyone changed the differential oil on a HT1800; doing the work yourself? If so, please tell me how you did it. My kit is a 2011. I've got 50,000 on my kit now and want to change the oil.
 
I'll be following this thread, SolidBob had a method, but not I cannot find the post. That area of the trike is a dog to get to, my nearest trike shop is almost 2 hours, and hard on the wallet.
 
I'll be following this thread, SolidBob had a method, but not I cannot find the post. That area of the trike is a dog to get to, my nearest trike shop is almost 2 hours, and hard on the wallet.

I'm in the same boat with installer 2 1/2 hr away. But, I will figure out something but was hoping someone/Roadsmith could give me some "tricks" to do this. Also, I don't know whether this rear end has a gasket or not. If it does then I need the correct info on the rear end so I can get one.

I wish Roadsmith would put a magnetic drain plug in the rear end since they are modifying it anyway.
 
I just got a phone call from a fine fellow that some of you might know, who knows a bit about the Roadsmith trikes. He should be along shortly to answer your questions. His screen name is MR TRIKE and it is a very fitting name. ;)
 
Roadsmith diff oil change

Has anyone changed the differential oil on a HT1800; doing the work yourself? If so, please tell me how you did it. My kit is a 2011. I've got 50,000 on my kit now and want to change the oil.

Hello- There is a brass drain plug in the bottom of the diff. Use a allen wrench to remove and drain, then replace brass plug. Take out threaded fill plug before draining then with a long transmission funnel, add NO MORE than 1(one) quart of 80w90 gear lube. That amount will fill diff. to about 1 inch below inspection/fill hole. Thats where it should be." Keep- on- Ridin"
 
Hello- There is a brass drain plug in the bottom of the diff. Use a allen wrench to remove and drain, then replace brass plug. Take out threaded fill plug before draining then with a long transmission funnel, add NO MORE than 1(one) quart of 80w90 gear lube. That amount will fill diff. to about 1 inch below inspection/fill hole. Thats where it should be." Keep- on- Ridin"

Thank you so much for the info. I looked but didn't see a drain plug so I will get under it again. The owner's manual doesn't cover this so I hope they update it.

BTW, love my RS trike !
 
Hello- There is a brass drain plug in the bottom of the diff. Use a allen wrench to remove and drain, then replace brass plug. Take out threaded fill plug before draining then with a long transmission funnel, add NO MORE than 1(one) quart of 80w90 gear lube. That amount will fill diff. to about 1 inch below inspection/fill hole. Thats where it should be." Keep- on- Ridin"

Yes, Mr. Trike, the man who started RS, and thanks for the post. I recall when we first met, couldn't believe you were behind the desk, I had to ask someone. We had a great conversation about when you first started with the RS brand, salute to you sir.
 
Ok, here's the skinny

Info was correct. Drain plug is located on bottom of differential approximately 1 1/4" from rear of diff. Drain plug requires 3/16 Allen wrench. Fill plug at top rear requires 1" hex socket.

Drain plug can be difficult to see because of road grime, etc. I had to wipe bottom of diff housing off to see it. Be careful not to over tighten when reinstalling. Drain plug should be flush with bottom of housing.
 
Bringing this thread back up with some tips.

I just did the rear gear oil change on my 1800 Roadsmith.

Here are a few tips that might make it easier for those wanting to do this:

1. A swivel socket extension is your friend in order to remove that 1" fill plug.

2. An outboard motor plastic gear oil pump (Walmart?) makes filling the chunk a breeze. Actually, I see no other way to get the new fluid in there without it. FYI: It will not pump in the full quart, so I added an additional amount of fluid to the bottle to compensate for what originally remained in the bottom after the pump quit pumping and that worked out to get a full quart in there.

3. One of those small telescoping magnets (Harbor Freight?) to the center of the fill plug will make it easier to reinstall and start the threads properly. It's a pain otherwise trying to get your fingers in there to hold & turn it with the frame in the way.

4. Just a tiny pin-head sized drop of BLUE (not red) Loctite to the drain hex plug threads gives that little bit of extra assurance it's not gonna vibrate loose.

Hopefully, this helps someone down the road.

LJ
 
Thank you for this info. I'm going to look at mine today..........See if I can find the plugs up on the shaft and then purchase all needed materials to complete the job.........:clapping:

Ronnie
 
Bringing this thread back up with some tips.

I just did the rear gear oil change on my 1800 Roadsmith.

Here are a few tips that might make it easier for those wanting to do this:

1. A swivel socket extension is your friend in order to remove that 1" fill plug.

2. An outboard motor plastic gear oil pump (Walmart?) makes filling the chunk a breeze. Actually, I see no other way to get the new fluid in there without it. FYI: It will not pump in the full quart, so I added an additional amount of fluid to the bottle to compensate for what originally remained in the bottom after the pump quit pumping and that worked out to get a full quart in there.

3. One of those small telescoping magnets (Harbor Freight?) to the center of the fill plug will make it easier to reinstall and start the threads properly. It's a pain otherwise trying to get your fingers in there to hold & turn it with the frame in the way.

4. Just a tiny pin-head sized drop of BLUE (not red) Loctite to the drain hex plug threads gives that little bit of extra assurance it's not gonna vibrate loose.

Hopefully, this helps someone down the road.

LJ

Is there room to get on your back get and up under there, or did you jack yours up a bit? I've been dreading that job. Car ramps maybe?
 
Is there room to get on your back get and up under there, or did you jack yours up a bit? I've been dreading that job. Car ramps maybe?

I have a full 1500# motorcycle/trike/ATV table lift that obviously makes it quite a bit easier to access this than sitting on the ground.

However, I would think getting the rear tires up on some car ramps or maybe some supports to frame somehow would give ya enough clearance to do it from the ground.

FYI...that little drain plug is hard to see. I had to clean off some substantial road grime just to find it, but it is there. The fill plug is the PITA, but a swivel and a telescope magnet will help a lot. I could find no other way to get the fluid in there other than my outboard motor gear oil pump, then I had to find a bottle that it would thread to....LOL. I was beside myself for a while. Whole job didn't take an hour though once I had everything in order. It took an hour because I let it drain/drip for a while.

Too bad you're not a little closer. We could put it up on the lift and have it done in a snap, and I'd be glad to assist ya.
 
Many thanks for that kind offer, nice ride to LA might not be so bad, looks like a bear of a job if you ya don't have the right tools, etc. I was thinking car ramps since I have them, but then would the oil drain? I'm thinking the drain is on the rear, the trike would be uneven toward the front. I need to give this some thought.
 
Many thanks for that kind offer, nice ride to LA might not be so bad, looks like a bear of a job if you ya don't have the right tools, etc. I was thinking car ramps since I have them, but then would the oil drain? I'm thinking the drain is on the rear, the trike would be uneven toward the front. I need to give this some thought.

Yeah. Slanted on the ramps probably wouldn't let it drain the way you'd want.

If you got the rear tires on the ramp, then maybe jack the front up to where it levels out some....just long enough to do the job?

Another thought: IF you know anyone with an open-frame car hauler trailer? Drive it onto the trailer and maybe work from beneath the trailer?

Maybe check around and see if someone local has a lift that you could use?

Anyway, I know it's a long ride to get over here, but you're more than welcome to come to my shop and we'll get er done. :)
 
Thanks for this information..it does help!



I have an idea that may help.. I'm very new to triking, (only 500 miles under my belt) so I'm no expert here...

BUT

What I did to change motor oil was [maybe this will help with gear fluid as well]: I had a 10ft 2x10 board, that I cut 6 - 12inch pieces from and took two boards and glued and screwed them together... So now I have (3) four inches high boards, I LIFTED THE BIKE UP AND PLACED THE BOARDS UNDER EACH WHEEL...

This gives me four inches of more room under bike to work with.. I found this made it much easier, to replace my oil, as well as the filter.... I'm not sure if this will help with gear fluid replacement, as I'm only at the 500 miles point, since the trike conversion on my 2010 Honda 1800.

Ronnie
 
Hello- There is a brass drain plug in the bottom of the diff. Use a allen wrench to remove and drain, then replace brass plug. Take out threaded fill plug before draining then with a long transmission funnel, add NO MORE than 1(one) quart of 80w90 gear lube. That amount will fill diff. to about 1 inch below inspection/fill hole. Thats where it should be." Keep- on- Ridin"

Mr. Trike, At what intervals should the differential oil be changed? -Miles / Age ?
 
Diff oil

Some very good tips here. I've had my RS only since last Sept. Is there a good place to put a Jack to raise rear end?
 
Not many good responses to this thread. I finally gave up and and took mine to a nearby Moto Trike builder, sure as h** wasn't cheap, but he got it done. Considering I'd have to make a run to Daytona, I guess the price was right. Just very hard to get up there to the filler plug.
 
Some very good tips here. I've had my RS only since last Sept. Is there a good place to put a Jack to raise rear end?

M2102 - you can use the lower shock mount (coil-over shock), the main 2-1/2" main cross-tube, or the 1/4" steel differential mounting plate. Do NOT lift using the driveshaft, the differential, nor the differential stabilizer bars. As with any of these types of jobs, be certain everything is secure before starting maintenance. Let me know if you need more info or help!

Jim
 
M2102 - you can use the lower shock mount (coil-over shock), the main 2-1/2" main cross-tube, or the 1/4" steel differential mounting plate. Do NOT lift using the driveshaft, the differential, nor the differential stabilizer bars. As with any of these types of jobs, be certain everything is secure before starting maintenance. Let me know if you need more info or help!

Jim

Jim,

Any chance of showing a couple of pictures here, of where both of these plugs are located??

and at what mileage or time do you recommend this rear end change??

Thank you,

Ronnie
 
Roadsmith are you there? Could you please post a picture of where these two bolts are located? With the size Allen wrenches needed, as I'll be replacing my fluid soon when it warms up a little..

Thank you!

Ronnie
 
Roadsmith, Are you there!!!!

Please if you can hear me, answer me!!!

Ronnie
 
Roadsmith, Are you there!!!!

Please if you can hear me, answer me!!!

Ronnie

first, read posts #5 and #8. Oil should be changed at 50,000 miles.

The filler plug on the differential is on the rear, top right portion of the diff. The access hole is cut into the trailer hitch support plate; can't miss it.

I gave a description of the drain plug location and Allen wrench size required.
 
first, read posts #5 and #8. Oil should be changed at 50,000 miles.

The filler plug on the differential is on the rear, top right portion of the diff. The access hole is cut into the trailer hitch support plate; can't miss it.



I gave a description of the drain plug location and Allen wrench size required.

Aaaaa Ok thank you, I only have (just checked yesterday) approx. 10,000 miles since I triked her out... so I guess I'm ok, for another season...My bikes been sitting in a cold garage all winter season. (on a trickle charge, with all wheels off cement floor).. I just changed oil/filter yesterday (cause I didn't get a chance to replace before she started her winter hibernation.... Todays supposed to be record breaking high 70* so I have a feeling all of us will just have to take our bikes out for that "needed' spin today.. Thank you for this information, I looked yesterday and couldn't find the filler plug, so early this morning I just REread your helpful hints, here, so I'm going to go back out in garage and look again..

Thank you, thank you, thank you!

Ronnie
 
FWIW, I'm bringing this thread back to life.......again.

When I did the gear oil change over a year ago, I added 1 quart of fresh 80-90 gear oil per the RS specifications.

Over time, I noticed that I would get 2-3 drops of oil leakage around the pinion seal when the trike sat for awhile....like maybe 4-5 days or more.

I'm pretty anal about my stuff and IF it leaks, I'm gonna fix it. So, I've been planning on changing out the pinion seal.

I called RS last week and got the pinion seal part# for my model. (National 8181NA). I had to order it and none of the local part houses had one in stock.

However, while waiting on the seal to be delivered, I was perusing some threads on this subject here on TrikeTalk. I came across another thread: "Differential leak" by OLD DAWG where he actually took his trike to The TrikeShop - Daytona where Dan did a seal replacement for him and recommended that only 3/4 of quart be added back in to the differential rather than a full quart. The reason being is that a full quart can overload the seal once the oil gets hot and will cause it to fail.

So just for giggles, I went ahead and drained the differential again and measured out exactly 24 ounces (3/4 of a quart) and added that amount back in. I cleaned up the area around the pinion seal in order to be able to watch for future leaks. Buttoned everything up and rode it over 300 miles; some interstate, back roads and in town. Put it back up on my lift and checked the pinion seal area this morning....dry as a bone....just the way I left it after the change...no sign of a leak. :clapping:

So the replacement seal is to arrive later today, but I think I'm gonna hold off on changing it till I see what happens.

IF it stays dry, obviously I'm not gonna change it. IF not, I will have the replacement seal in my possession and will do the replacement over the winter.

I have a feeling it will no longer leak and stay dry....we shall see.

I reposted this so that anyone that's planning on doing a gear oil change, that the amount is 3/4 of a quart to save on the seal.

Hope this helps someone.

Everyone ride safe.

LJ
 
FWIW, I'm bringing this thread back to life.......again.

When I did the gear oil change over a year ago, I added 1 quart of fresh 80-90 gear oil per the RS specifications.

Over time, I noticed that I would get 2-3 drops of oil leakage around the pinion seal when the trike sat for awhile....like maybe 4-5 days or more.

I'm pretty anal about my stuff and IF it leaks, I'm gonna fix it. So, I've been planning on changing out the pinion seal.

I called RS last week and got the pinion seal part# for my model. (National 8181NA). I had to order it and none of the local part houses had one in stock.

However, while waiting on the seal to be delivered, I was perusing some threads on this subject here on TrikeTalk. I came across another thread: "Differential leak" by OLD DAWG where he actually took his trike to The TrikeShop - Daytona where Dan did a seal replacement for him and recommended that only 3/4 of quart be added back in to the differential rather than a full quart. The reason being is that a full quart can overload the seal once the oil gets hot and will cause it to fail.

So just for giggles, I went ahead and drained the differential again and measured out exactly 24 ounces (3/4 of a quart) and added that amount back in. I cleaned up the area around the pinion seal in order to be able to watch for future leaks. Buttoned everything up and rode it over 300 miles; some interstate, back roads and in town. Put it back up on my lift and checked the pinion seal area this morning....dry as a bone....just the way I left it after the change...no sign of a leak. :clapping:

So the replacement seal is to arrive later today, but I think I'm gonna hold off on changing it till I see what happens.

IF it stays dry, obviously I'm not gonna change it. IF not, I will have the replacement seal in my possession and will do the replacement over the winter.

I have a feeling it will no longer leak and stay dry....we shall see.

I reposted this so that anyone that's planning on doing a gear oil change, that the amount is 3/4 of a quart to save on the seal.

Hope this helps someone.

Everyone ride safe.

LJ

Good info. My pinion seal was replaced under warranty after if blew out and leaked oil everywhere when going down the road. When I changed I use the one quart and so far no leaks. Hope it stays that way. :)
 
Diff oil change

FWIW, I'm bringing this thread back to life.......again.

When I did the gear oil change over a year ago, I added 1 quart of fresh 80-90 gear oil per the RS specifications.

Over time, I noticed that I would get 2-3 drops of oil leakage around the pinion seal when the trike sat for awhile....like maybe 4-5 days or more.

I'm pretty anal about my stuff and IF it leaks, I'm gonna fix it. So, I've been planning on changing out the pinion seal.

I called RS last week and got the pinion seal part# for my model. (National 8181NA). I had to order it and none of the local part houses had one in stock.

However, while waiting on the seal to be delivered, I was perusing some threads on this subject here on TrikeTalk. I came across another thread: "Differential leak" by OLD DAWG where he actually took his trike to The TrikeShop - Daytona where Dan did a seal replacement for him and recommended that only 3/4 of quart be added back in to the differential rather than a full quart. The reason being is that a full quart can overload the seal once the oil gets hot and will cause it to fail.

So just for giggles, I went ahead and drained the differential again and measured out exactly 24 ounces (3/4 of a quart) and added that amount back in. I cleaned up the area around the pinion seal in order to be able to watch for future leaks. Buttoned everything up and rode it over 300 miles; some interstate, back roads and in town. Put it back up on my lift and checked the pinion seal area this morning....dry as a bone....just the way I left it after the change...no sign of a leak. :clapping:

So the replacement seal is to arrive later today, but I think I'm gonna hold off on changing it till I see what happens.

IF it stays dry, obviously I'm not gonna change it. IF not, I will have the replacement seal in my possession and will do the replacement over the winter.

I have a feeling it will no longer leak and stay dry....we shall see.

I reposted this so that anyone that's planning on doing a gear oil change, that the amount is 3/4 of a quart to save on the seal.

Hope this helps someone.

Everyone ride safe.

LJ

Good info on oil change. The location of the plugs on diff case and location of the case, how did you get the measured amount of oil put back in? Snake a flexible hose from fill hole to a high point on the outside or even under the seat?
 
Good info on oil change. The location of the plugs on diff case and location of the case, how did you get the measured amount of oil put back in? Snake a flexible hose from fill hole to a high point on the outside or even under the seat?

Buy one of those hand pumps designed for quart/gallon jugs. I bought a quart of correct oil and simply pumped it from bottle till empty. Other than laying under the trike and working in a twisted pretzel position it was easy peasy. :)
 
FWIW, I'm bringing this thread back to life.......again.

When I did the gear oil change over a year ago, I added 1 quart of fresh 80-90 gear oil per the RS specifications.

Over time, I noticed that I would get 2-3 drops of oil leakage around the pinion seal when the trike sat for awhile....like maybe 4-5 days or more.

I'm pretty anal about my stuff and IF it leaks, I'm gonna fix it. So, I've been planning on changing out the pinion seal.

I called RS last week and got the pinion seal part# for my model. (National 8181NA). I had to order it and none of the local part houses had one in stock.

However, while waiting on the seal to be delivered, I was perusing some threads on this subject here on TrikeTalk. I came across another thread: "Differential leak" by OLD DAWG where he actually took his trike to The TrikeShop - Daytona where Dan did a seal replacement for him and recommended that only 3/4 of quart be added back in to the differential rather than a full quart. The reason being is that a full quart can overload the seal once the oil gets hot and will cause it to fail.

So just for giggles, I went ahead and drained the differential again and measured out exactly 24 ounces (3/4 of a quart) and added that amount back in. I cleaned up the area around the pinion seal in order to be able to watch for future leaks. Buttoned everything up and rode it over 300 miles; some interstate, back roads and in town. Put it back up on my lift and checked the pinion seal area this morning....dry as a bone....just the way I left it after the change...no sign of a leak. :clapping:

So the replacement seal is to arrive later today, but I think I'm gonna hold off on changing it till I see what happens.

IF it stays dry, obviously I'm not gonna change it. IF not, I will have the replacement seal in my possession and will do the replacement over the winter.

I have a feeling it will no longer leak and stay dry....we shall see.

I reposted this so that anyone that's planning on doing a gear oil change, that the amount is 3/4 of a quart to save on the seal.

Hope this helps someone.

Everyone ride safe.

LJ

I can tell you that Dan is the guru of Road Smith builds, if he says 3/4 of a quart, you can take that to the bank.
 
I can tell you that Dan is the guru of Road Smith builds, if he says 3/4 of a quart, you can take that to the bank.

If the owner's manuals were up to date then we would all know the correct amount to use. Every mfg. manual I've seen is sorely lacking in useful and accurate information.
 

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