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Redline Trailer Hitch Accessories Redline Trailer Parts

Redline


Redline has become the industry leader in trailer parts and accessories through their dedication to customer service. They pride themselves on having parts in stock, shipping orders the same day they were placed, shipping orders correctly and being competitively priced.

  • Offers a full line of trailer products for enclosed, utility and boat trailers
  • Manufacturers toolboxes, wiring and trailer jacks
  • Produces top-quality products at unbeatable prices




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Expert Answers about Redline

  • Trailer Suspension Hanger Kit with the Most Lift for Tire Clearance Under the Trailer Bed
  • The # APT4 Tandem-Axle Hanger Kit will provide about 4 inches of clearance from the center of the trailer axle to the bottom of the trailer frame, with no load on the axle. This is assuming that your axle tube is 3 inches diameter. If your axle tube is smaller the height will be sightly less. The curve of the springs you select will have some affect also. I would recommend that you go with the APT5 hanger kit because all of the hangers are the same height and it will make it easier to...
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  • Placement of Front and Rear Hangers When Building a Tandem Axle Trailer
  • To determine the location for the front and rear hangers on your tandem axle trailer you will first need to make sure that you have the correct center point for your equalizer hanger. The center point of your equalizer hanger needs to be located where you will have 60 percent of the frame of the trailer in front of the center of the equalizer hanger and 40 percent behind the center of the equalizer hanger. For example, if the trailers frames length is 10 feet, then the center-line location...
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  • Choosing/Sizing the Correct Trailer Ramp Spring for a Ramp Door
  • When selecting ramp springs for a trailer ramp, you will want to know the diameter of your hinge pin and how much space you have available in the hinge. A typical horse trailer or utility trailer ramp uses 3/4 inch hinge pins and would require two ramp springs with a 3/4 inch inner diameter. The ramp springs that we carry fit 1-1/2 inch diameter hinge pins and are designed for use with heavy-duty steel ramps like those on equipment trailers or car haulers. The spring slips over the...
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  • Removing and Replacing Trailer Spindles
  • To replace a spindle, the old one would need to be cut off, and the new one welded into place. This is NOT a job for the do-it-yourselfer. The new spindle must be absolutely square with the axle in order to prevent premature tire wear and wheel tracking problems. I would recommend finding a welder who is experienced with trailer axles. Your local RV dealer or repair facility could probably refer you. In many cases, it's less expensive to simply replace the trailer axle itself. We offer...
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  • What is the Correct Tire Air Pressure For a ST205/75D15 Tire
  • Special trailer (ST) tires should be inflated to the maximum air pressure that is stamped on the sidewall of the tire. It will be stamped with a designation of maximum load at a maximum psi. For example, the Redline ST205/75-D15 Bias Ply Trailer Tire and Wheel, part # TW15BIAS5ON475, that you have referenced is a load range C tire. It has a maximum capacity of 1,820 pounds at 50 psi. That means the tire is capable of carrying up to 1,820 pounds of weight if you have it filled to the...
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  • How to Determine Hub and Spindle Size
  • The spindle dimensions are as follows: A is the mounting dimension, B is the seal dimension, C is the inner bearing surface, D is the outer bearing surface and E is the diameter of the threaded portion of the spindle for spindle nut selection. Say you need a spindle and hub for a wheel with 5 on 4-1/2 inch bolt pattern and an axle that is 3500 lbs. For a single axle trailer you can use two of either the item # R20484, if your axle is round or item # SP20484 if your axle is square....
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  • Torque Rating Requirements for Installing Leaf Springs on a 7000 lb Tandem Axle Trailer
  • The torque requirements for leaf spring u-bolts depend on the diameter of the u-bolts that are being used. If the gross weight of your tandem axle trailer is 7,000 lbs, then you likely have two 3,500 lb axles. Typically 1/2 inch diameter u-bolts are used with leaf springs for 3,500 lb axles and they have a torque rating of 45 ft/lbs to 70 ft/lbs. The shackle bolts do not require a specific torque rating because tightening the shackle bolts too much will squeeze the shackle straps against...
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  • How to Determine the Capacity of Trailer Leaf Springs and How to Raise the Coupler Height
  • Leaf springs typically have the part # stamped on the strap that holds the leafs together at one end of the shorter leafs, or it is painted on the concave side of the springs. The part number can then be used to determine the capacity of the springs. Generally springs with any age on them will be very hard to get a part number off of. You would then need to go by the axle capacity to determine the spring capacity, which would be 1/2 of the axle capacity. If you have a 3,500 lb capacity...
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  • Where to Install Shackle Straps and How to Determine Axle Position When Building an ATV Trailer
  • For a 3,500 Dexter Straight axle the springs should be placed between 16 and 18 inches on center from the hub face (flat area the wheel mounts against). Placement of the spring centers in any other position will reduce the axle capacity. If you are using a different brand of axle you will need to contact the axle manufacturer for the full capacity spring center dimensions. If you are using double eye springs then the shackle straps will be located at the rear of the springs. The top...
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  • Constructing an Axle from Pipe and Spindle for Use on Homemade Trailer
  • The Redline Spindle # R104BT8 that you referenced has a 1-1/4-inch diameter stub that is 4-inches long. This spindle will fit an axle beam (pipe) with a 1-1/4-inch inner diameter. While you can certainly fabricate your own axle to go on your homemade trailer, assuming you have access to a qualified welder, I suggest you consider buying a complete axle assembly from etrailer. Apart from the savings in time and labor you also benefit from knowing the exact capacity of that system, something...
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  • Parts Needed to Convert a Single Axle Marine Master Trailer to a Tandem Axle Trailer
  • We do have tandem axle suspension kits, leaf springs and u-bolts to convert a single axle trailer to a tandem axle trailer, but the conversion will be a little more involved than just adding a second axle. To ensure you purchase the correct parts, you will want to look at your current axle and suspension. You will need to know the axle weight capacity, axle diameter and leaf spring dimensions to choose the correct suspension parts for a tandem axle trailer. I have attached a link to all...
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  • Parts Needed to Add Electric Brakes to a Utility Trailer with a 3500 Lbs Axle and Brake Flanges
  • You will need several items to add electric brakes to your Carry-On Utility trailer. Starting with the trailer you will need a hub and drum that matches the bearings and seal on your trailer spindle and your wheel bolt pattern. The only way to be sure is to check the bearing part numbers and seal part number, but with a 3,500 lbs Dexter axle that has brake mounting flanges you will most likely have the # L44649 Outer and # L68149 inner bearings and # 58846 seal. If these are the correct...
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  • What is the Torque Requirement for 1/2 Inch U-Bolts for Trailer Suspension
  • According to our FAQ on slipper springs, linked for referenced, the torque specs are as follows: Torque Ratings 1/2 inch Bolts: 45 ft/lbs - 70 ft/lbs 9/16 inch Bolts: 65 ft/lbs - 95 ft/lbs 5/8 inch Bolts: 100 ft/lbs - 120 ft/lbs The Replacement U-Bolt, # 1753223, uses a 1/2 inch nut so it would fall into the 45 to 70 foot pound category.
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  • Raising the Height of a Travel Trailer that Rides Close to the Ground
  • If the leaf spring stack on your travel trailer is currently mounted to the bottom of the axle, there is an over-under conversion kit that you could use to gain a few more inches of height. However, this will change the center of gravity on the trailer and can lead to an increased chance of trailer sway. For 3 inch round axles you could use # K71-385-00. And for 2-3/8 inch round axles use # K71-384-00. You should not have to do any welding to use these kits. You would not want to...
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  • Can Trailer Axles Be Mounted Above and Below the Leaf Springs on a Trailer
  • The best and safest way to have the axles orientated to the leaf spring is the way the trailer was originally manufactured. The trailer manufacturer will have tested the trailer with the original suspension setup for adequate braking and handling performance. If you flip the axles it could work fine, but since it has never been tested it is hard to say for certain. With that being said, you can have the axles on the top or the bottom of leaf springs. If you do have the axles on top of...
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  • How to Measure to Select the Correct Brake Shoes for a 6,000 lb Dexter Trailer Axle
  • You will need to measure to select the correct brake assemblies for your axles. You need to know that the brake assembly is compatible with the brake mounting flange and with the drum's diameter and depth. I added a photo showing how to measure a hub/drum for you, Typically 6,000 lb Dexter axles have a 5 bolt brake flange, like part # 4-44-1, and utilize 12 x 2 inch brake assemblies, like part # 23-106. The correct brake shoes for these assemblies are part # BP04-150. If you measure...
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  • How to Determine the PSI Rating of an Aluminum Trailer Wheel
  • Without knowing the psi capacity of your wheel it is hard to say whether or not you will exceed its rating. I have talked to our trailer wheel manufacturers before and they have said that the wheel almost always will have a higher psi capacity than any tire that will fit the rim. Of course there are exceptions. If you check your current wheels you should be able to find the rating. On alloy wheels, it is usually stamped into the metal on the back of the wheel somewhere. It can be difficult...
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  • 5th Wheel Trailer Pulls Nose High Are Spacers Available to Level with My 2011 2500 Dodge Ram Diesel
  • The first thing I would do in your situation is take the truck and trailer to your RV dealer and have them check out your setup. Typically 5th wheel trailers are set up to tow a bit pin high to allow for more weight transfer to the rear most axle or axles on the trailer. If possible, you can adjust the trailer pin box closer to the underside of the trailer loft, or reduce the height of your fifth-wheel hitch head in the bed of your truck. Be aware that adjusting the trailer too close...
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  • Spring Hanger Spacing Dimensions for a Tandem Axle Slipper Spring Suspension on a 14,0000 lb Trailer
  • The hanger spacing for a tandem axle trailer suspension setup can be determined, but you need to take into account the axle spacing needed for the overall diameter of your wheel and tire combination and the springs you will be using. Lets say that you plan on using 4 of the 5-Leaf Slipper Springs, # SP-232275, for 7,000-lb Trailer Axles, and that your wheel and tire combinations are the Karrier ST235/85R16 Wheel and Tire, # AM32764. The AM32764 wheel and tires overall diameter is...
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  • Replacement Trailer Ramp Springs
  • We have several hinge pins like # HP412G that I have linked for you, but it sounds like you need actual springs. We have some heavy duty ramp springs like # RS16933RH and # RS16933LH if you happen to have a heavy duty equipment trailer like what they haul tractors and other large equipment on. For an open utility trailer you may be able to use a tailgate assist like # RA-27C. Or for an enclosed trailer we have springs that are similar to garage door systems. I have linked those as well....
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  • How to Pick Out Replacement Hubs for a Boat Trailer
  • In order to pick out the correct hub assembly for a trailer you are going to need know a few key pieces of information. The first thing you will need to know is the bolt pattern of your hubs. Since the figure you came up with doesn't match any of the 5-bolt bolt patterns I am going to need to to recheck your bolt pattern. For further info on this check out the FAQ article I attached on this. Next thing you will need to know is what spindle you have on your trailer. In order to do that...
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  • Electric Trailer Brakes Lock Up When Trailer is Plugged in to Tow Vehicle
  • The easiest first step here would be to try the trailer on a different truck, and see if the same problem occurs. If the trailer brakes are free until the trailer is plugged in, I suspect that something is mis wired. I would suggest examine the wiring where the break away system was bypassed and make sure that the 12-volt accessory feed is not connected to the brake wire at some point. Are you by chance using a 7 to 6-way adapter? If so, there are two accepted ways of wiring a 6-way...
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  • How Does The EZ Lube Spindle # R20384EZ Work On A Boat Trailer
  • On the EZ Lube Spindle # R20384EZ you do not need a grease fitting for the hole on the inside end of the spindle. This is an EZ lube spindle which is designed to allow you to put grease onto the bearings by using the zerk fitting on the threaded end of the spindle. You will not want to block the hole that is on the inside end of the spindle. When the hub is installed on the EZ lube spindle it will form a cavity around the wheel bearings and when you pump grease into the spindle through...
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  • How Tight Should Shackle Bolts Be Tightened On Trailer
  • There should be enough free play in the shackles to allow them to move. There is no specific torque rating for shackle bolts. The first thing you should make sure of is that the bolts you use are long enough so that when installed you will have at least 2 threads protruding from the nut. Next, make sure that the nut you are using is a locking nut, so that it cannot work loose and fall off. If the bolt you are using has knurls at the bolt head you will want to tighten the bolt...
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  • Solutions for adjusting Gooseneck Trailer Height for Towing with a Truck with Lifted Suspension
  • There are things that can be done to raise your gooseneck trailer suspension to help provide the proper ride height for your truck. First the capacity of the axles on your trailer should be determined, to be sure that the parts ordered will work correctly and will be safe. We have a informational article on double-eye trailer suspensions that should be helpful. If your axles are 3 inch diameter, then we could use a Trailer Springs Over-Under Conversion Kit, # K71-385-00, to move the...
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  • Clips and Clamps to Attach Wires and Wiring Harnesses to the Bottom of a Trailer Frame
  • There are many ways you can secure wires to a trailer. I would not recommend the use of tape as it will wear out quickly when exposed to the elements. Soldering is also not recommended because it is a more permanent method and you may need to change wires or move them in the future the hot solder would also melt the coating on the wiring, causing a short. If you can find some large enough, wire ties could be a simple solution. We have several clamps and clips that could work for this...
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  • What is the Maximum Amperage Draw of Trailer Brake Magnets on a Tandem Trailer with Four Brake Drums
  • Maximum amperage draw for 4 Brakes that are 10 or 12 inch diameter is 15.0 to 16.3 amps at 12 to 13 volts. The 14 gauge wire may be sufficient but for maximum braking effectiveness at full load capacity. I would opt to run 10 gauge wire. Larger wire will only help the effectiveness of the trailer brake system and 10 gauge is what we use when installing trailer brakes even on single brake axles with 7 inch brake assemblies. We offer Jacketed 2 Wire, 10 Gauge, Brake Wire, item # 10-2-1,...
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  • How to Install the 7-1/2 Inch Round Butterfly Vent # 371800 on an Enclosed Trailer
  • To install the 7-1/2 Inch Round Butterfly Vent, # 371800, you will need to drill or cut a hole in your trailer that is 5-7/8 inches diameter to no more than 6 inches diameter. If you have access to a hole saw this size for a drill the wold be the cleanest way to cut the hole. A smaller hole could be used, but the butterfly may rub on the trailer sides if a smaller hole is used. The mounting holes on this vent are 4-9/16 inches on center and the distance between the inside of any two...
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  • Spring Hanger Spacing with the Tandem-Axle Trailer Hanger Kit for Double-Eye Springs # APT9
  • The distance on center between the spring hanger bolt holes for dual axle setups, with the # APT9 Tandem-Axle Trailer Hanger Kit, should be 29-1/2 inches for double eye springs that measure 25-1/4 inches on center between the spring eyes and for axles that are 3 inches in diameter. This will put your axle spacing somewhere between 33-1/2 and 34 inches. You will also need to determine the position of the axles before welding the spring hangers into place. The general rule of thumb for...
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  • Ramp Spring Weight Capacity and Left or Right Hand Orientation for a Horse Trailer
  • The right hand ramp spring, item # RS16933RH, and the left hand spring, item # RS16933LH, are differentiated by paint on the springs from the manufacturer. The springs with green paint on them are right side springs, left side springs are unpainted. Right side springs will go on the right side of a ramp and left hand springs go on the left side of a ramp. Both right and left hand springs deflect in the same direction the designation of right and left has to do with orientation of the stick...
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