Pinion seal on Viper conversion

[pwhoever]

I ran into a buddy a couple weeks back at a Meet and Greet in Custer, SD. He recently acquired a used Goldwing with a Viper conversion and we began discussing each other's. He mentioned about his getting a pinion seal leak and having to replace his pinion seal because of the leak and asked if I had any issues with mine. I'm at 6 years since I had my conversion done and hadn't noticed any issues. He took a peek where driveshaft goes in to the rear end and said he can see where there was a dirty film build up and that mine will probably need to be replaced in the near future.

I had taken my trike out there in my toyhauler and didn't notice any drips on floor. I did probably over 1000 miles total on trip and still no drips. Even after getting back home and unloading, still the toyhauler floor was dry. Since the trip, I have driven it another 7-800 miles and now I'm seeing drips on garage floor. I looked underneath and can see the plate under the differential is wet with gear oil. So the next step is to get to the pinion seal and tackle this.

The only thing I've done to rear end recently was to replace the gear oil prior to the trip out west. I followed the CSC recommendation and used a conventional gear oil. The one I used was Castrol Limited Slip 80W-90 and it also was API GL-5 rated so it should have been fine.

I will be calling CSC in the morning to order the seal. My buddy mentioned that a special tool is needed for the seal which he bought and is going to loan to me to use. But I was wondering if maybe I can source the seal locally. I seem to remember the installer mentioning something about the rear end on my 2016 Viper being a modified Dana (Chrysler possibly?) rear end but not sure. Also does anyone have any tips and clues about doing the pinion seal replacement? Any help would be greatly appreciated...

[pwhoever]

Well I called CSC on Tue and ordered 2 seals just to be safe. I should be receiving them them sometime today. I also reached out to my buddy and he is going to ship his specialty tool to me soon as well as some literature he received from CSC that has torque values for the various items. I'm hoping to dig into this next week. I'm going in kind of blind because although I have average mechanical skills, I've never tackled anything related to rear ends before. During the phone call to order the parts, I also ended up talking with Will I think??? during the call to CSC for parts.

He gave me some basic info that I should be able to use but without ever doing anything rear end related before, I'm not sure that I understood everything he was telling me. What would be nice is if I could get ahold of a repair manual for these rear ends but not sure if one even exists. What would be helpful is knowing the actual brand of the rear end. Like I mentioned before, pretty sure that these have Dana rear ends but without knowing the specific model, it will probably be a challenge. Luckily, nowadays with YouTube, I should be able to find something close to help guide me...

[pwhoever]

Well I'm a little closer now to figuring this out. The new seals came today and I was able to get a part number to do a Google search. The seal part# is DVL-94751 After a Google search, I came up with a pdf that discusses the driveshaft retro and I think this will have a lot of the information I need.

It discusses pulling out the old seal with the previous driveshaft setup and installing new seal and driveshaft. As mine already has the newer version of driveshaft already, I only need to be concerned with the 2nd part of the instructions. I knew about the changeout from earlier trike versions but didn't even think about checking this out...

https://img1.wsimg.com/blobby/go/196...=1657805450940

[Jack Klarich]

Upload a picture of your rear end if you can

Lube the outer and inner lip of the new seal with just a bit of gear oil or bearing grease before installing the seal

Look for any burs or knicks on the yoke before installation

Good Luck and report back

[pwhoever]

I decided to try getting a little disassembly started and found that the gravel pan is an absolute bear to remove. Looking at the installation instructions, the gravel pan and subframe get installed prior to installing the rear end and body. At that point, it's all exposed and easy to do. Not so much after everything is in place. There is seriously limited room and you are working blind trying to hold the bolt and get the nut removed.

And mine were installed the opposite of the directions. The directions call for the bolt to go in from underneath and nut on the top. Mine were bolt going down and nut on bottom of the pan. My thoughts are that if the bolt was installed going up into the pan, at least that would have helped guide the socket onto the nut which is also a bit taller than the head of the nut. But by trying to get the socket onto the head of the nut by feel, it was extremely difficult. I am going to try and do it the right way when reinstalling. For reference, the nut and bolt were both 7/16".

I did finally get the gravel pan removed to expose the rear of the driveshaft. And now at least have a better idea of what has to be done. And I discovered that there are slight differences between the standard driveshaft and the ones fitted with ABS. Mine has ABS.



This pic shows the difference between an ABS and Non ABS. The non ABS uses nuts on rear of ujoint brace only. The ABS one uses Allen head bolts on front, spacers between the ABS ring, and a bolt on the rear.



This photo shows the rear of my driveshaft with arrows pointing to the 4 bolts I will need to remove. Not sure yet if I need to remove the ABS sensor holder to remove the seal but I plan on doing it anyway. First because I want to get it cleaned up and get all the grime off it. Second, because when the sensor and mount were installed, the wiring harness was routed so it got caught under the subframe and trapped by the gravel pan. I am going to route it above the lower arm of the subframe and zip tie it.



And this photo is a pic showing all the leaking gear oil that coated the front lower part of differential and the bottom of the differential plate.

I am supposed to be receiving the tool tomorrow in the mail from my buddy to help with installation of the new seal. I am planning on doing the driveshaft disassembly tomorrow afternoon and hopefully will have the new seal installed as well as getting it all put back together.

[pwhoever]

Well the tool did get here today and got a chance to use it much later in the early evening. My buddy said he bought the tool direct from CSC when he had to replace his seal. It's pretty slick and would have worked well except for a small problem that I will come back to later.

I finally dived into this fully today. I started off by draining the gear oil. I left it alone so as much gear oil would drain as possible. Just an FYI, it takes a 3/4" socket for the drain bolt.

It was then time to tackle the driveshaft. As I mentioned earlier, I have the ABS ring so it is a bit different setup than the standard. I don't know what size nut is on those but for ABS equipped, it is an Allen head bolt on the aluminum shoulder and a collar behind yoke, ABS ring, and then a nut. The ABS ring is 2 halves. The Allen head bolt uses a 1/4" Allen wrench or bit and the nut is a 1/2" nut.

Before removing any of these bolts, I made a mark on the yoke, the particlar face of the ujoint there, and the aluminum shoulder so I can mate them up all the same way they came apart. I had been told that sometimes once this is is undone, there is enough play and the driveshaft can sometimes be pushed towards engine and comes out of the yoke. Of course, that wasn't the case for me.



So the next thing I needed to do was to remove the ABS sensor. The sensor is attached to a mount attached to the face of the rear end. The sensor is mounted to this by 2 Allen headed bolts and secured by 12mm bolts. The Allen wrench to use for this is 4mm. Once bolts are out, the sensor just pulls out.

So now it was time to get the driveshaft disconnected. In order to do this, I had to loosen the 4 bolts attaching differential to the large plate.



The heads of the bolts on mine were 9/16" and the nut were the same. I only loosed the bolts but didn't remove them. Mine were pushed all the way in the slots to the front. I was able to persuade the differential backwards so bolts were about midway in the slots and that was enough to separate the driveshaft and ujoints from the yoke. I did have to do some light prying to get them to separate. Once they were, I moved the driveshaft to the right and up. I secured it by zip-tying it out of the way.



Once that was out of the way, it was now time to remove the yoke. It is secured to the rear end shaft by a 1-1/8" nut. An impact tool is pretty much mandatory to get this off. My buddy said he took the opportunity to pick up a cordless one from Harbor Freight. I already had an air impact wrench so I used this. My compressor will fill to almost 140psi and I had to wait until it was there to get this done. I had to hit the nut with the air wrench several times until it finally started spinning off.



Finally it was time to get the old seal removed. It is in there good. No easy way to get it out and I pretty much destroyed it getting it out. I had to get creative and used a hammer and screwdriver first to punch holes in it and begin prying it. It began to come out in pieces. The final thing I did after getting a bunch of small pieces off was to get a set of 90⁰ needle nose pliers in there and just continue to pry. It did finally come out and didn't damage any of the surface where the seal is mounted. I'm sure there must be a better way but I didn't have that knowledge



After getting the old seal out, it was time to get the new one in. I used the tool I borrowed. I put a coating of gear oil all around the rubber center of new seal as well as all around the outer edge. The new seal fits right onto the face of the tool and then the tool goes over the shaft of the rear end. The silver nut that comes with the tool is then supposed to be used to tighten the tool, again using an impact wrench, but it kept getting a bit too tight for me just threading it on by hand and I was worried about stripping threads so I used the yoke nut instead.



This seemed to work well and I was sure that the seal was fully seated but it wasn't. I would estimate that I was able to get the seal almost all of the way in except for a very slight lip. Not sure if it is visible in the next photo.



Earlier in this project, besides removing the ABS sensor, I was going to also remove the mount to clean it up. I found that these are Allen head screws that use a 3/16" Allen wrench. I was able to finally get the very top screw to come loose as well as the bottom one but not the middle one. They are in there extremely tight and with the limited space, it was extremely hard but finally cracked loose.

The middle one is going to be a problem. No matter what I did, it would not break loose. Then the worst possible thing to happen did. The screw head began to round out. I tried to find a slightly larger Allen wrench to fit but it wouldn't work. I then tried a T-30 torx bit. I was able to hammer it in and attached a socket wrench but that ended up spinning out as well. Now I have to figure out another solution. I'm going to try picking up a Dremel or similar tool tomorrow now that I have an excuse.

But not being able to remove this caused another problem. The seal driving tool is slightly larger than the seal. The ABS sensor mount goes right up to the edge where seal is. I found out that this is why the seal didn't fully seat. So this mount is going to have to come off one way or another or I won't be able to get the seal install finished. I did try using a small block of wood and hammer to try lights tapping but it didn't work.

I will figure this out somehow...

[Jack Klarich]

Very good so far

Polish the yoke area that passes thru the seal and give it a very light coat of lube before install

[pwhoever]

I am just taking the day off for a day or so just out of frustration but will get back to it shortly. I like to finish up on a win and that didnt happen yesterday.

One thing very lacking in the documentation is any kind of tool list or sizes used. This ends up taking some time to figure out the wrench sizes, socket sizes, etc... This can get a bit confusing as the front half of these Goldwing trikes are all metric and all the rear stuff is SAE. All rear stuff that is except for the screws holding the ABS sensor to the mount but I'm assuming that's because they used the one from back of the GL1800. And the directions are pretty general and not very detailed at times. Most of the stuff is simply directions without many visuals. A few more would have been helpful.

[pwhoever]

I should add that there really is no official "guide" by CSC for replacing the pinion seal but much of the information can be found in that driveshaft retrofit download. And calling up CSC and speaking with Will always results in more good information. However it would have been nice to be told that the ABS mounting bracket needed to be removed before using the tool to push in the new seal. I wouldn't be in this spot had I known...

[pwhoever]

Sorry, just thought of 2 things I didn't mention in above posts.

I have seen you tube videos that say besides marking the ujoint and yoke shoulder positions I mentioned above, it's not a bad idea to mark the nut position on the yoke to make sure it gets put on in the same way. Unfortunately, I only marked the ujoint stuff. But I was told that when reinstalling nut onto yoke, get it snugged down and just hit it a couple more times for a couple seconds and it "should" be good. I will find out when I get my seal issue taken care of.

And when removing the nut off the yoke spindle, a good trick to keep yoke from spinning and be more effective, have someone step on the rear brake lever and that will keep it locked up. Since I'm doing this by myself, I couldn't do both so I stepped down on brake lever and used a bunch of wood shims in between the brake lever and the foot peg mount. It worked perfectly.

[Jack Klarich]

Sorry, just thought of 2 things I didn't mention in above posts.

I have seen you tube videos that say besides marking the ujoint and yoke shoulder positions I mentioned above, it's not a bad idea to mark the nut position on the yoke to make sure it gets put on in the same way. Unfortunately, I only marked the ujoint stuff. But I was told that when reinstalling nut onto yoke, get it snugged down and just hit it a couple more times for a couple seconds and it "should" be good. I will find out when I get my seal issue taken care of.

And when removing the nut off the yoke spindle, a good trick to keep yoke from spinning and be more effective, have someone step on the rear brake lever and that will keep it locked up. Since I'm doing this by myself, I couldn't do both so I stepped down on brake lever and used a bunch of wood shims in between the brake lever and the foot peg mount. It worked perfectly.

That is a torque prevailing nut and should actually be replaced ( similar to CV axles)

You can use a pipe wrench with an added pipe on the handle placed against a concrete floor to remove and replace the nut

[pwhoever]

That is a torque prevailing nut and should actually be replaced ( similar to CV axles)

You can use a pipe wrench with an added pipe on the handle placed against a concrete floor to remove and replace the nut

Great... now to figure out a part # to replace this.

[Jack Klarich]

Great... now to figure out a part # to replace this.

It is not an absolute to replace the nut, some do and some don't

Any good Auto jobber should have an assortment of nuts to choose from be it a pinion nut or a CV axle nut, if not available you can reuse the original

Is yours a Ford type rear end?

If so your local Ford dealer probably has one in stock

[pwhoever]

Not completely sure which rear end it is. I was told once that it's a custom Dana rear end made specifically for CSC trikes but no confirmation one way or the other. Maybe California Sidecar could pop in and clarify seeing as how this is supposed to be a Direct Factory Support subforum...

[Sidecarbill]

Most rear ends have a crush sleeve between the bearings, if you over tighten that nut and crush that sleeve bearing preload will be to tight. To much preload can smoke the bearings. If the nut isn't tight enough it can allow the pinion to move ruining the gear set.

[pwhoever]

Most rear ends have a crush sleeve between the bearings, if you over tighten that nut and crush that sleeve bearing preload will be to tight. To much preload can smoke the bearings. If the nut isn't tight enough it can allow the pinion to move ruining the gear set.

I believe these do have that. In the directions for the retro installation, the directions mention a torque value of 185 ft lbs. However in the directions that my buddy received, it mentioned 20-30 ft lbs. I called up Will at CSC to clarify and I remember him saying something about getting a washer seated the first time around needed the 185 ft lbs.

But tightening up after a seal change should only be around 20-30 ft lbs. He said the key is to spin the yoke several times prior to removing the yoke to get a feel for its tightness. Then when reinstalling it, tighten it just enough for the same feel. #14 in the directions mentions this. These are slightly different from the directions I posted and downloaded from CSC. I am trying to post the directions from my buddy.

[pwhoever]

Ok, looks like they pulled a switcheroo after my phone call and now have the updated instructions online. Here is what I originally saw. Notice the info in #12 of the instructions:

[Jack Klarich]

I believe these do have that. In the directions for the retro installation, the directions mention a torque value of 185 ft lbs. However in the directions that my buddy received, it mentioned 20-30 ft lbs. I called up Will at CSC to clarify and I remember him saying something about getting a washer seated the first time around needed the 185 ft lbs. But tightening up after a seal change should only be around 20-30 ft lbs. He said the key is to spin the yoke several times prior to removing the yoke to get a feel for its tightness. Then when reinstalling it, tighten it just enough for the same feel. #14 in the directions mentions this. These are slightly different from the directions I posted and downloaded from CSC. I am trying to post the directions from my buddy.

Are you sure that 20-30 ft lbs is not the rotational torque it takes to rotate the pinion after the 180 ft lbs is reached?

[pwhoever]

Are you sure that 20-30 ft lbs is not the rotational torque it takes to rotate the pinion after the 180 ft lbs is reached?

Fairly sure as Will repeated the same info when I talked to him. But he added to first use impact to snug nut down on yoke, then spin it and it will move too easily. Hit it with a couple more blasts of impact wrench and the yoke should now feel the same while rotating as it did prior to yoke removal. So maybe the 20-30 ft lbs is just a guesstimate and the true torque value is an UNK. It does seem rather on the low side. It is more about how it feels which is supposed to be more accurate per CSC than actually torquing it down??? Hopefully I'm able to recall exactly how it felt prior to yoke removal.

A lot of verbal info, vague directions, and lots of unknowns. Can't say as I'm very happy to be going through this and will be glad once I'm successfully done.

[Sidecarbill]

Reread the instructions it's inch pounds not foot pounds. That would be for the rotational torque of the pinion assembly. That's usually done with the ring gear out.