harrydirty

Put together a Harbor Freight 40x48 utility trailer for C6Z track tires and tool box; started using it in May 2011 and have done six track days so far. Everything went well except when I was coming home from the last track date. I started hearing a lot of banging sounds when we went over bumps. I stopped several times to check but found nothing loose.

Finally got to check it out the other day and found that the bolts that mounted the MDF deck to the trailer were loose, enough that I could lift one corner of the deck a half inch from the trailer frame! This was in spite of using locking nuts (plastic ring at the end of the nut threads). Just to be sure I checked all other nuts and bolts but the only ones that loosened seemed to be the plywood deck mounting bolts. Maybe the mount points started to compress on the plywood, loosening the bolts?

Anyway, I will check all trailer bolts every 5 or 6 track days of usage just to be sure.

sperkins

Double nut/Locktite

RX-Ben

I used nylocks and I still lose bolts. I also drive in NYC. 10 miles there is more wear/tear than the rest of my trip (whether it be 100 or 700 miles).

76stingracer

The bolts compressed the wood. I tighten mine once a year on my tire trailer.

racerbob4

Big washers with lock washers and loctite and nylocks.

PA Z06

Good idea will look at my tire trailer before it gets put away for the winter

c4cruiser

The bigger the washers the better to keep from compressing the plywood. You can use some fender washers for the plywood side. You can even use some 1" wide by 1/8" thick aluminum flat stock to place around the edges of the plywood. Drill holes every foot or so and use nylock nuts or nuts and lockwashers underneath. You can also file the holes square after drilling and use carriage bolts.

When I had my HF trailer, I used some 1" 90 degree angle aluminum stock to trim out the edges of the plywood. Made it look a lot better and I didn't have to worry about the plywood edges being beaten up or gouged.

TRACKMAN2

a problem i can defianatley solve!!!! dich the mdf..(medium density fiberboard) it cant stand up to water basically cardboard!!! get a sheet of pressure treated 3/4 ply or 1/2 inch mdo (exterior grade paper backed plywood) cariage bolts lock nuts and washers...away you go

RX-Ben

I have lock washers and nylocks. Still lost some bolts.

c4cruiser

The next step would be to use some red threadlocker to the bolt threads and tighten. The red stuff requires heat to release the compound.

RDnomorecobra

that's what i did. I wouldnt use anything other than pressure treated plywood

NealB

I have used that type of trailer for autocross tires since 1986. I strongly recommend you add metal to reinforce the basic framework of the trailer

I was driving down the interstate and had the tongue pull loose from the front of the deck but remain attached at the center of the trailer. Resulting tail-wagging-the-dog finally ripped the tongue off at the rear also and let the deck/tires/wheels/tool box catapult thru the center median at 75mph while I drove on dragging the tongue

Found that the metal at the front of the trailer where it bolts to the tongue fatigued and ripped out. All bolts were still tight in the remnants

I build another one and before installing decking, bought mild steel angle iron from Lowe's and welded it to triangulate the tongue to the bed and the basic rectangular shape of the bed

All was fine for two years until a leaf spring mount point ripped off the side rail, thankfully at only 20mph. I then took 1/4" thick by 3" angle and reinforced the side rails where the leaf spring mounts attach along the entire length.

You are cruising for a disaster unless you reinforce the dangerously thin metal on those trailers

RX-Ben

Agreed.
I welded in steel sections to the bottom of the trailer for the tongue mount - both sections were fatigued (metal was split btw the bolt holes). Triangulation is the real fix here, as noted.

Thanks for the heads up on the leaf mounts.

c4cruiser

Another thing to consider with the HF trailers is the "quality" of the bearings. When I bought mine some 6 years ago, the first thing I did was to remove them and check for any pitting or galling. I found there was very little grease in them.

Even the model with the 12" wheels will see the wheel turning faster at freeway speeds. The 8" wheel will spin even faster.

The bearing size on these trailers are common so it might be a good idea to get a good set of replacement bearings to include the races. Use a high quality wheel bearing grease and inspect and clean and re-grease every season. Keep an eye on the tires for any signs of cracking. Doesn't hurt to have the wheel/tire assembly balanced and checked for true.

longdaddy

i've used one for 4 years and put probably over 15k miles on it, at least half of those at 70+mps speeds, NOT recommended by wheel/tire manufacturers, but what do they know. I have original bearings. I do clean and re-grease them every 2k miles or so. 12" wheels - I would NOT do 8".

I have put up to 8 wheels/tires on mine (4x8 trailer that I shortened to about 4x6 by not using all the frame pieces) with no issues. I do not use the deck, just some padding over the frame which holds up the tires. All bolts that hold the frame together have locktite on them and I never had one come loose.

I did not want the small one due to the tongue construction - 4x8 has 2 piece tounge that halves the load on the metal and doubles the number of things that need to fail at the same time for exciting stuff to happen - I like that. Plus I wanted to be able to take 8 wheels

Overall the reliability of the trailer (for the money) has been fantastic. Go China.

EDIT: If I did want to go full paranoid (as opposed to my usual 45%), I would indeed heed the advice above about leaf spring mounts. Once you feel good about the tongue*, that is probably the next weakest link.


*that's what she said

RX-Ben

What is the process for cleaning/replacing the wheel bearings?

I haven't touched my bearings - around 15k miles, most around 72mph.

95jersey

One question, where did you find a hitch for a C6Z aluminum frame?