Replacement Brakes and Hubs for 1987 Moody Boat Trailer with 7 x 2-1/4 Hydraulic Brakes

Updated 08/15/2018 | Published 08/14/2018

Products Featured in This Question

Hydraulic Brake Kit - Uni-Servo - Free Backing - Dacromet - 10" - Left/Right Hand - 3,500 lbs

(365)

$191.41

Dexter Hydraulic Trailer Brakes - Uni-Servo - 7" - Left/Right - 2.5K

(153)

$232.86

Question:

My trailer currently has 7” diameter brakes with 2-1/4 shoes. You guys don’t carry this size. Can I replace them with your 10” brakes. Will the four bolts on brake assembly be correct. Can you give me those measurements along with bearing diameter.

asked by: Travis

Expert Reply:

The 4-bolt mounting pattern of 7-inch brakes is the same as for 10-inch brakes; both use bolts/holes spaced apart by 2-7/8-inches on center.

Moving to larger brakes will naturally require new hubs and these new hubs must use the same set of bearings and the same wheel bolt pattern as your current ones. Also note that larger brakes and drums will be compatible with different wheel diameters than your 7-inches brakes were. The free-backing 10-inch hydraulic brakes you referenced, kit # AKFBBRK-35-D which is rated for 3500-lb axles, is compatible with 13, 14 and 15-inch wheels. 7-inch brakes like # 23-398-399 are typically compatible with 10, 12 and 13-inch wheels.

New larger hubs must use the same bearings as your original hubs in order for them to fit on your spindles. The linked photo shows the usual location of bearing part numbers which will help us find compatible hubs. If you tell me your inner an outer hub bearings I can see what we have to offer in a compatible 10-inch hub/drum. I linked our main page for hub/drums where you can click on your inner and outer bearing numbers to see compatible items.

Another option is to replace the entire axle with a new one that includes new flanges, brakes, hubs, bearings, races, etc. I linked our axle page too. You can select the appropriate axle weight capacity based on the trailer's GVWR and axle dimensions. This option gives you the opportunity to switch to electric drum brakes which are more and more common as OEM parts on boat trailers since they cost less and are much easier to install.

expert reply by: Adam R