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Replacement Sidewind Gear Kit for Bulldog or Fulton Jacks - 5,000 lbs

Replacement Sidewind Gear Kit for Bulldog or Fulton Jacks - 5,000 lbs

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Bulldog Trailer Jack,Camper Jacks - BD500106
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Replacement gears work for Bulldog or Fulton sidewind jacks with 5,000-lb capacity. Call 800-298-1624 to order Bulldog accessories and parts part number BD500106 or order online at etrailer.com. Free expert support on all Bulldog products. Guaranteed Lowest Price and Fastest Shipping for Replacement Sidewind Gear Kit for Bulldog or Fulton Jacks - 5,000 lbs. Accessories and Parts reviews from real customers.
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Bulldog Accessories and Parts

  • Trailer Jack
  • Camper Jacks
  • Gear Parts
  • Gears
  • Bulldog

Replacement gears work for Bulldog or Fulton sidewind jacks with 5,000-lb capacity.


  • Replacement gears work with Bulldog or fulton sidewind jacks that have 5,000-lb capacity
    • Designed for use with Bulldog series 139, 159 and 170 jacks
    • Also fits Crown jacks with capacites of 2,000 lbs, 3,000 lbs or 5,000 lbs
  • Kit includes all that you need to replace or repair gears


  • Overall gear diameter: 1-3/8"
  • Shaft diameter: 1/2"
  • Gear thickness: 45/64"
  • Pin length: 13/16" and 1-1/4"
  • Pin diameter: 3/16"
  • 15 Teeth per gear

Product dimensions

500106 Bulldog Gear Kit for Sidewind Jacks - 5,000 lbs

Item # BD500106

California residents: click here

Video of Replacement Sidewind Gear Kit for Bulldog or Fulton Jacks - 5,000 lbs

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Bulldog 5000lb Jack Rebulid

Today, we're going to be taking a look at the rebuild process on the Bulldog 5000-lb capacity jacks. These are typically considered to be the 170 series jack. You're going to have the square top with the metal cap. This is going to be a side-wind configuration. They've got excellent replacement part solutions available regardless of whether you've messed up your handle, the bearing or the gear set to allow you to completely rebuild this jack without having to replace it. It's a really nice, straightforward process.

The gears are going to be part #BD500106. Gives us our base gear. Gives us our handle gear. It's going to give us the pin for our handle and the pin for our base gear. That's a nice, straightforward setup. We're also going to have our bearing with thrust washer.

This is going to be part #BB500223. You'll see that's going to be a shielded bearing, so if water wants to enter the top of the jack, that shields it, takes it around it. You can see the bottom. That's designed to rotate. As we operate our jack, that's going to give us a very, very smooth, friction-free operation.

We also have a handle replacement part number. This is Part #BB500105. This is going to be a direct replacement. It's got that bell-shaped handle. It's a very comfortable handle.

It's going to give you the bushings that go in each side of the jack, and it's also going to give us the pin there. Let's get our parts set aside. Of course, we're rebuilding a brand new jack here, so we're just going to reuse the parts that we take out. We'll start by removing our cap here on top. We've got an 11mm socket. We just want to take both of these lock nuts off. You don't have to worry about holding the other side. These are carriage bolts. Once those are off, take out our two pins. Pull off our cap there. This typically doesn't get damaged, but in case it does, we also have that available on our website. The part number you'll need to replace this is BD500205. Once that is off, you'll see it's going to give us a pretty good look right into that gear set. Want to take a little bit of the grease off of it there. Then, when we put this back together, we are going to fully grease it back up. We just need an all-purpose grease. It doesn't have to be any kind of high-temp this or that. Once we've got most of that out of the way, we're going to see as we turn our gear, it's going to be like a little half-moon shaped cutout. You'll see a pin in there. It's going to go all the way through. That's the pin that we need to remove. That's what's holding our gear and our handle in place. Typically, for this, you'll use a punch. This is a 5/32nds punch. Just start tapping that through. Once we've got that pin driven through, we'll get it set aside. You can see that's going to cause our handle to move pretty freely, so we'll pull that out as we hold on to our gear there. Now, when we remove our side gear, they're both pretty much the same, the top and the bottom gear, but our pin needs to go through the pass-through area for our handle, and it needs to go through the non-pass-through area for the base gear. We'll pull that one off now. You can see that just that little pin that just floats in there. Pull that out, and that's going to match the other pin that came with our gear set. You can also see on each side here, you've got one there and on there are going to be our handle bushings. If you need to replace those, you just tap these out and put your new ones in place. Then we're going to be ready to pull the inner tube of the jack out of the outer tube. You'll see as we do, you'll see the screw start to sink down in there, just like that. We've got our washer there that we're going to hang on to. We'll reuse that. If we continue to pull and separate, there on that underside, we've got our thrust washer there and our bearing that rides on top. You'll see the design of the jack. It's pretty simple. It's just a really large machine-style screw. That's probably never going to give you failure. The typical failure either comes from our bearings, our gears or our handle. That's why they make them readily replaceable, very easy thing for you to do. Once we have that off, we would take our new thrust washer and bearing. We can drop it down on there. I think it's also a good idea to spread a little bit of grease on that screw. Certainly isn't going to hurt anything, let that work its way through. While we've got it out, we might as well just help our bearing out a little bit, throw a little bit of grease in there. Now we're ready to take our outer tube and slide it back on the inner tube. Now there's an indention on the side of the outer tube that we need to line up with the long groove on the inner tube, just like that. We'll bring that on down, see our screw right there on the top, come right through. We'll take our washer. That's going to slide on. We've got our floating pin. Slide that into place. Want to make sure that's about equal amounts hanging out on each side. We'll place that lower gear on. Again, our gears are the same, but we want to be sure we capture that pin inside that closed opening. We'll grab our handle. It's going to come back through. We'll slide our gear in place there so it goes through that. It's going to come all the way through that outside. You can see the opening in our bearing there. We just need to line that up with the hole that's in the handle. Once we've got those aligned, we'll slide our pin back in. You saw it was about flush with the outside of the gear when we took it apart. You can leave it there. I just like to knock it down in to where it's about 50/50. All right. Now we'll cap it off just by sliding our new cap down into position. Re-insert our carriage bolts there. Now, you want the head of these bolts to be on the same side as your handle. That way, you won't have anything sticking out there you might get your fingers stuck on or something like that. Now, we don't have to crush this like crazy or anything. We just want to get those down to where they're snug. That's all there is to it. That's going to complete the rebuild side of it. You'll see the hole that's been drilled all the way through the base here, or that inner tube. This is designed to accept accessories. We have two available. One would be Part #BBCP555. It's going to be the wheel. Nice, heavy-duty wheel. Just simply take that clip off, slide it on to your jack. Slide your clip back through and secure it in place. That's going to help you keep your trailer mobile. It's a nice, larger wheel, so it should roll over things. You'll see it's got good width to it. Also, we've got Part #BD018564. That's going to be a removable foot plate. It uses the same style pin. It will slide right down on there. This is just to help spread or dissipate that energy out over a greater area so we don't have to worry about our inner tube here sinking down into the sand, the mud, the gravel, even the asphalt, things like that. We hope this shows you how with just a few simple tools and a few inexpensive parts, we we're able to completely rebuild our Bulldog jack rather than purchasing a new one.

Customer Reviews

Replacement Sidewind Gear Kit for Bulldog or Fulton Jacks - 5,000 lbs - BD500106

Average Customer Rating:  4.8 out of 5 stars   (86 Customer Reviews)

Replacement gears work for Bulldog or Fulton sidewind jacks with 5,000-lb capacity.

- BD500106

Parts worked perfectly in my jack. Very easy to install. It was far better and cheaper than replacing the jack.

It is still working without any issues.
Donald G - 08/04/2021

- BD500106

This is the wrong kit for a Fulton 5000 lb jack. The gears are too small, in my case the broken part was the smaller pin, so I was able to use that one piece and get everything working with the old parts.

- BD500106

Excellent product and package tracked for delivery.

- BD500106

Quality parts. Fast shipping. Good prices. I will be ordering more in the future

- BD500106

Great news fellow 5th wheel backyard mechanics! If you're looking to repair/replace the bevel gears of an MPD 71125 Atwood/Lippert standard duty 5th wheel landing legs instruction manual, you're in luck. These gears are nearly a direct replacement. The only real modification needed is to enlarge the dowel pin thru hole of the vertical bevel gear you'll be attaching to the 1/2" drive shaft. It will need to be enlarged to 13/64 in order to reinstall the dowel pin. For my replacement, I also belt sanded the back side of the drive shaft gear to reduce the thickness from 45/64" to 5/8" to match the OEM part although I found this to not be necessary. Because I did, I used a .095" thick brass washer to back-up the gear and fill in the gap between it and the worn drive bushing in the outer housing. Once completed, pack the drive gears with lots of extreme pressure grease and you'll be good-to-go.

- BD500106

After the kids over cranked the boat trailer jack and snapped off teeth on the gears, I thought I would have to buy a whole new jack. Instead I found your web site and was able to easily find the replacement gears that fit exactly. The trailer jack has worked perfectly since and I could not be happier with my purchase and the performance of your product. Thanks.

- BD500106

The shipping was overall pretty fast, so that was nice. The replacement parts were for a Fulton jack. However, the gears ordered were just a bit bigger than what was in the jack previously. I fought getting all the parts in the jack and getting everything to match up as the gears were a bit thicker/taller than what I was replacing. Luckily, after a hour or two of fighting it, including attempting to grind one gear down on the backside, since only one old gear was broke, I just used one new gear and one old gear, so then I had enough clearance for the handle to slip back inside. It was a bit frustrating that both gears could not be used, but I guess I have a spare now if the new one gives out sometime down the road. But happy in the end not to have to buy an entire new jack for just these simple little pieces.

- BD500106

The replacement gear set for my bulldog tongue jack works great. I did have to shim the side gear to get proper clearance and gear engagement, no shims in the old one, maybe that is why it failed.

- BD500106

This product was referenced in an on-line article, as an option for repairing older Atwood landing gear (1996 Jayco Eagle SL211) for which parts have become obsolete. For my particular application, the pin slots required some alteration as the original Atwood pins needed to be reused due to hole sizes in the shafts. Aside from the alterations, all other dimensions performed as a direct fit. Landing gear was repaired and re-installed in less than an hour. YMMV Thanks to the original poster for their share of product application, Thanks to etrailer.com for expedient service and shipping. We are on the road again!

- BD500106

As dicribed. fit and worked well.

- BD500106

I ordered this gear for the jack for my pontoon boat trailer. When it arrived it was easy to replace within minutes solving a very aggravating problem. Thank you etrailer.com for helping me out.

- BD500106

This product worked perfectly to replace the gears that had stripped on my trailer jack. I was glad to find a replacement gears for my Shelby heavy duty trailer jack.

- BD500106

product as described super fast shipping. thank you for your fast service. thank you

- BD500106

Part arrived when it said it would and worked great on replacing the gears on the Atwood landing gear I was repairing. Had to make some minor adjustments on the drill press for the undersized pin groves the Atwood application called for.

- BD500106

Perfect fit replacement. These parts are what was expected, however in general the design is weak and I will likely be purchasing replacements again in the future. That is not an eTrailer issue, but just the facts of the design.

- BD500106

This fixed a long term problem with the tongue jack on our 1986 camper. Operates very smooth as previous gears were completely worn down and this was the only site I was able to find these parts.

- BD500106

great product ,fast shipping, thanks for saving me lots of $ having replacement parts. you guys are the best.

- BD500106

The product I order was just what I needed. The picture with dimensions was the most helpful of all...and shipping was spot on with the tracking provided. Repaired my Bulldog trailer jack fast and easy. I would recommend this web site to anyone!

- BD500106

Thanks to etrailer offering replacement gears for my side wind jacks I saved from buying new ones and throwing more things away just because of a wear part wearing out. Every store I called told me the same thing ..."we've never heard of any one replacing the worn gears...buy new jacks. Thanks etrailer for offering the parts and fast delivery. All I would say is to be sure of the hole size in your old jack handle and screw, one of my screws had a smaller ID than the new pins that came with the gears. No big deal.

- BD500106

Great company to work with. Quick response and shipping. As always a great bunch to deal with.

- BD500106

I returned the purchase today. It was the wrong part for what I needed and was able to locate it locally. I was pleased with the ease of ordering and shipping time. Will not hesitate to order from this company again if the need arises.

- BD500106

Amazing! I ordered 6 different parts, and all of the orders for cancelled because the part is discontinued. Etrailer had this part that was ALMOST an exact match, but it got the job done. Thanks etrailer!

- BD500106

Got the product I needed with all parts included at a good price. Especially since I needed to expedite which is expensive. The low cost of the actual item helped. Received on the expected date in perfect condition. Even got a notification minutes after the item was delivered. Great service for an online company. Only suggestion would be having the ability to ship using our company fedex account.

- BD500106

Hey, You guys were great. The first one was not a correct fit ut you listened to my description and got it right. Thanks for your patience as the second set of gears fit perfect.

- BD500106

Was very happy with the speed of finding me the correct part. even when all I had was a description of the jack I was working on. Very friendly staff. Will use them again in the future.

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