Rebuilding a Tandem Axle Trailer with 6,000 Lb - 7,200 Lb Axles

Question

Question:

4- 6" drop in deck height would be too much. Now that I have trailer in front of me 0-4" would be fine if possible? As for modifications the fenders are going to be replaced so consider the trailer with fenders removed. As for the 6 spring hangers that are welded to the trailer frame those too will be removed. Most of the bolt holes are worn oval/elongated. Some of the mounts have been repaired and not squared when welded? So I had planned to cut them all off and weld on new. So basically it's a clean slate 6"×2" C channel frame, my 2 axles and 4 springs. My best guess is the axles are rated @ 6-7000 lbs each? The tubes are 3", 14.5"×8" wheels, 12" brakes, 1" threaded ends, outer bearing app,1.25," inner bearing 1.5" Leaf Springs; 25.25" long, app. 2" wide. spring ends and eyes are 1.75" and equalizer; app. 3" vert. for ends. equalizer 3" vert. 5.75 horz. I will mention again that I plan to replace all the susp mounts/equalizers with new. I was hoping you could suggest using a shorter? longer? taller? or wider mounts/ equalizers that will possibly help to lower the trailer or at least not raise ìt? Same goes for the axle U bolts that I also will be removing and replacing with new. The axles are and will be mounted on top of the leaf. If it is possible for me to buy extra long U bolts with taller seats or blocks that would raise the axles?? and lower the trailer 1-2-3 or possibly even 4"?? Again, or a least not make any higher? on that inner axle bearing I should have mentioned that its 1.75" and tapers to 1.5"

asked by: Edmond

1

Helpful Expert Reply:

I would love to help but are you sure that you have space to lower the trailer 4" - 6"? You will need at least 3" from the top of the tire to the bottom of the fender in order to allow for proper suspension travel. It looks like the fenders on the trailer now will not allow for this therefore I would you to do some measuring before any of the new parts are purchased.

I would also need more info on the trailer such as axle capacity (see center label), leaf spring length (eye to eye), leaf spring width, hanger height, equalizer dimensions, shackle strap dimensions, etc. These are going to help me make sure you get the correct replacements for you needs. Until then I would not be able to provide you with part numbers as it would be just mear guesses that could end up requiring a ton of modifications.

expert reply by: Conner L

1

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Edmond

10/10/2018

4- 6" drop in deck height would be too much. Now that I have trailer in front of me 0-4" would be fine if possible? As for modifications the fenders are going to be replaced so consider the trailer with fenders removed. As for the 6 spring hangers that are welded to the trailer frame those too will be removed. Most of the bolt holes are worn oval/elongated. Some of the mounts have been repaired and not squared when welded? So I had planned to cut them all off and weld on new. So basically it's a clean slate 6"×2" C channel frame, my 2 axles and 4 springs. My best guess is the axles are rated @ 6-7000 lbs each? The tubes are 3", 14.5"×8" wheels, 12" brakes, 1" threaded ends, outer bearing app,1.25," inner bearing 1.5" Leaf Springs; 25.25" long, app. 2" wide. spring ends and eyes are 1.75" and equalizer; app. 3" vert. for ends. equalizer 3" vert. 5.75 horz. I will mention again that I plan to replace all the susp mounts/equalizers with new. I was hoping you could suggest using a shorter? longer? taller? or wider mounts/ equalizers that will possibly help to lower the trailer or at least not raise ìt? Same goes for the axle U bolts that I also will be removing and replacing with new. The axles are and will be mounted on top of the leaf. If it is possible for me to buy extra long U bolts with taller seats or blocks that would raise the axles?? and lower the trailer 1-2-3 or possibly even 4"?? Again, or a least not make any higher? on that inner axle bearing I should have mentioned that its 1.75" and tapers to 1.5"

Reply

Conner L.

10/10/2018

I understand you will be replacing the leaf spring hangers but the height of the existing ones you have now is still needed. These are going to be the main factor for lowing the trailer now so if you would like a 4" drop, then you would need to purchase a set of hangers that are 4" shorter than the existing. As you mentioned, you can also get an equalizer with a lower profile but this is not going to lower the trailer nearly as much. I do not recommend using lowering blocks as they can cause a very rough ride. For a suspension components kit with short leaf spring hangers and fairly low profile equalizers, I recommend the Tandem-Axle Trailer Hanger Kit for Double-Eye Springs part # APT3 (1). The front/rear leaf spring hangers are 1-1/2" tall and the center leaf spring hanger is 2-1/2" tall. If you take the difference between these measurements and the ones on your trailer, that is going to then give you an idea of how much height it will gain/lose. For the leaf springs, I recommend the 5-Leaf Double-Eye Spring for 6,000-lb Trailer Axles part # e34SR (4). These are actually 1-3/4" wide which I am almost certain is what you have on your trailer now. They are rated for a 6,000 lb axles which if the diameter of your axle is 3", then it would likely be either a 6,000 lb or 7,200 lb. If you have the 7,200 lb axle, the springs will bend more so than on a 6,000 lb axle which is going to drop the trailer even further so that's good news for you. For a set of u-bolts, I recommend the U-Bolt Kit for Mounting 5,200-lb to 7,000-lb, Round Trailer Axles part # APUBR-8 (2). The above parts are going to give you everything you need to rebuild the suspension on your trailer. However, it sounds like you are wanting to go even further and replace the brakes and hubs/drums. If that is the case then for the braking assemblies, I recommend the Electric Trailer Brake Kit part # AKEBRK-6 (2). In order to replace the hubs/drums I would need you to take more precise measurements of the spindle with a digital caliper like part # 301-17068 to the thousandth of an inch as we do not have anything that matches what you provided. Once you take these measurements you can find the correct set of hubs/drums using the attached selection. I have included a (#) next to each part which represents the quantity you need to order to replace everything on the trailer. I have also attached several review videos for you as well.

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Answer 1

The torque rating for 1/2 inch u-bolts in U-Bolt Kit, #APUBR-1, is a minimum of 45 ft lbs and a maximum of 70 ft lbs.

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Answer 2

The 10" x 2-1/4" Electric Brake Shoe/Lining #BP04-095 could possibly work, but I recommend going with the Replacement Shoe and Lining Kit for Manual Adjusting 10" Electric Brake Assembly #AKBRKR-S-10 instead because it is designed…

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Answer 3

You will need the Red LED Trailer Clearance or Side Marker Light #328-K-52 or Amber LED Trailer Clearance or Side Marker Light #328-K-51 for your 2018 Forest River Sunseeker motorhome. These lenses have the same Top Command SAE-AP2-16 markings on the…

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Answer 4

If you are needing the hub and drum assembly then you will want to go with the Dexter Trailer Hub and Drum Assembly #8-201-5UC3-EZ but if you are just looking for an idler hub then you will want part #8-213-5UC1 instead. These come with the correct…

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Answer 5

The manual lockout on your Atwood 85778 surge brake coupler is there so that you can back up the trailer without the brakes locking up on you. Yes you can safely tow your trailer with the broken manual lockout, you just have to make sure you…

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Answer 6

The old version of the #HBA-CAM used 4 wires, but the product was updated awhile back and now uses only two wires as shown in the photo on the product description page. The white wire from the HBA-CAM would tap into the white ground wire and the blue…

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Answer 7

I would love to help you upgrade the suspension on your Twilight 2800 travel trailer. The MORryde Rubber Equalizers for Tandem Axle Trailers #MR87ZR that you referenced are a great solution but we do need to double check a few things. First is that…

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Answer 8

The only way you could power interior dome lights on a trailer without it being connected to a tow vehicle would be to power the lights with a battery like a breakaway battery. How you choose to wire up the batteries will in the end be up to you, but…

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Answer 9

I've never heard of an actual third brake light connector on a camper shell to plug in on a truck and we don't carry any parts to do that. The light generally needs to be hardwired into the truck's brake light circuit. The issue with this…

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Answer 10

I did some checking and the hub/drum we offer that will work for you is the part #8-430-5UC3. This uses the same bearings as the 8-415 and will be an exact fit aside from the fact this is a non-ABS setup and the 8-415 came in an ABS setup and non-ABS…

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Answer 11

From what I could find it looks like your 122R (red) and 122Y (amber) lights measure 3.75" x 1.70" x .81". We don't have any replacement lense directly for the GLO-BRITE lights but we do have some similar lights that you could use…

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Answer 12

To tow your trailer that uses an RV style 7-way blade style connector with your semi that has a 7-pin connector, you need to construct an adapter that will also combine the brake signal into the right and left directional signal pins. This can be…

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