Disk brake question

[crackles]

I've been reading the threads on disk brakes being fitted - and some of the problems also. I like the idea of stainless steel disks and assemblies but cannot find a supplier in Sydney.

So I guess I have to try my luck with the sets available from WM, and I need to know which parts to order. WM require 1/ Wheel size (easy, 14"), current brakes (drum) hub size ( ??? ) and bolt pattern -which I think is 5 on 4.5". Trailer is a 2000 model.

Can anyone help with the hub size? Or for that matter, any other supplier / manufacturer who will export downunder?

Thanks once again.

Crackles

[Captain Steve]

Got mine from Champion, off their website. Price is good and the kit is made for the mac trailer...nothing else needed. Extensive installation guide can be downloaded from there too.

http://www.championtrailers.com/

[Chip Hindes]

Agree with Steve. Champion Trailers is the place to go; I used them exclusively for my single to double axle conversion. Mine's a 2000 as well. You can order just the disc brake upgades for your drums if you want for about $100 U.S. per wheel. Champion's prices are way lower than West Marine for the same items.

I had some trouble with mine, well documented in previous threads, Tie Down's problem not Champion's. Tie Down eventually made it good.

Download the catalog from their website, and they have an international order form. If you need them, the correct part numbers are on the copy of the order form I posted on this mod.

[crackles]

Thanks Gents.

Steve, I have since emailed Champion and now just waiting for that part of the world to catch up. I'm still not sure which is the correct part # to order, and hoping they do.


Chip, thanks. I was interested in your problem with Tie Down's. Question. Why the second axle? Do you really think it is necessary or just better? I am a former tyre man and I beg to differ with your point on mixing tyres. They will track differently and you may notice the trailer preferring to wander to one side or the other when motoring. The prime thing to look for on trailer tyres, is load rating. The higher the load rating, the better, with less "flex" in the side wall resulting in less chance of a blowout and longer wear. Light truck tyres (sorry, tires for you) are the way to go. Because there is no gerbox or speedo involved on a trailer, there is some flexibility in actual tyre (did it again, tire) size. So long as it is a correct fitment for the rim and clears the trailer/guard/brakes, pick the tire size you want.

Thanks to you both, again.

[Captain Steve]

When I ordered, I called them and just asked for the kit to put on a Mac trailer. they knew just which one to send. Put it on in 2003...only used in saltwater too!

[Chip Hindes]

Why the second axle? Do you really think it is necessary or just better?

Not completely necessary, but that depends on how the trailer is loaded. With no motor, empty, in the conguration wherin it can be towed by the legendary Ford Taurus, the trailer capacity is probably adequate. I've determined that with the 50HP motor, two batteries, some water, some fuel and all the other stuff I normally carry in my boat, the trailer is always overloaded by somehwere over 200 to as much as 800 lbs. I towed my boat to Florida and back (3000 miles total) for two weeks on the water. With the single axle in the heat of the summer, with empty tanks and as much extra stuff as I could fit in the tow vehicle to avoid overloading the trailer. At highway speeds of 65-70 mph, the bias tires got alarmingly hot, and one of them with less than 1000 miles on it lost a big chunk of the tread. No idea how, only know that it happened. Plus, the trailer behavior in crosswinds, when being passed by large trucks, etcetera was unacceptable to me.

My solution was to add a second axle and four wheel disc brakes. Since then I have towed my trailer to Florida and back two additional times, and you simply cannot believe the improvement until you've done it both ways.

Others have simply upgraded disc brakes, or upgraded to larger wheels and tires (that doesn't answer the overloaded axle question); a few have changed out for a higher capacity axle with wheels and tires. Any of these provides an added margin from the stock trailer configuration. Everybody has their own comfort lever for these things, and for those who have done them it may be enough. I consider them all indequate to the way I use my trailer. After towing with a Ford Explorer for over two years, when it came time to replace the Explorer I upgraded to a Ford Expedition for the same reason. Like the stock trailer, the Explorer worked, just not very well.

I have two "bad" things to say about the second axle. 1) There is no doubt that when making sharp turns, forward or reverse, the tires scrub and the trailer suspension loads up heavily. Knowing that the tires and suspension are loaded to just over half their rated capacity, I'll live with it. 2) In our country full of toll roads, it costs me more to travel the distances. I estimate maybe $40 extra each way to Florida.

I am a former tyre man and I beg to differ with your point on mixing tyres. They will track differently and you may notice the trailer preferring to wander to one side or the other when motoring.

I'm not mixing tires side to side. I have two radials on the rear axle, two bias on the front axle. The tires may behave differently on the different axles, in fact, I'm quite sure they do; at speed the bias tires still get a lot hotter than the radials. But on a trailer, even if the axles track differently, it's transparent to the behavior of the trailer. The trailer tracks straight as an arrow under all conditions. If/when I lose one of my bias tires, I'll replace both with radials. The spare will still be a bias; and I'll consider it for emergency use only.

I've done considerable research and I know all about tire construction, sizes, load and ply ratings and the different capacity rating systems, etcetera. There is in fact considerable disagreement among the "experts" concerning stiffer versus more flexible sidewalls for trailer tires, so I won't argue it here.

Light truck tires are not the way to go for this trailer. The highest capacity tire of any type you can buy for a 14" rim is the 215-75D14 ST (special trailer) which came standard on the Mac trailer for this year; 1870 lbs capacity each. There are no 14" LT tires rated for the same capacity. The only way to get adequate or better tire capacity for this trailer from any other tire, of any type or construction, is to upgrade to 15" rims. If your trailer came originally equipped with the 205-14 tires (earlier 26X trailers had these, 1760 pounds each) you can get a modest tire capacity increase by upgrading to the 215s.

One warning about the 215s: In the U.S. at least, you absolutely cannot find one at a tire store. BTDT. They will order one form a warehouse which can be in from 1-3 days, but that doesn't help at all when you're on the road trying to get somewhere. If you have these tires and no spare, you're asking for trouble.

[Simon]

I enjoyed reading that note Chip

Which is better for the Mac?

#1. Replace the original factory axle with a 15" rim 6000# single axle assembly (electric brakes).

#2. Add a second 3500# axle.

Thanks

S

[Chip Hindes]

You have lots of choices.

No doubt in my mind the second axle is better overall. You can get higher capacity either way, so that's not the question, but the two axle trailer will track better, and, if you "do it right" you have four wheel brakes instead of two. The cost of adding a second axle as opposed to changing out for a higher capacity single axle isn't substantially different; Either way you need a new axle, new brakes, wheels, tires and springs. The difference for the two axles versus one pretty much boils down to a new set of fenders and the additional brake lines. For me, since I switched my existing axle to disc brakes, it cost an extra $100 per wheel for the new brakes, plus the solenoid lockout, another $40.

If you're just going to change out, immersion is not recommended for electric brakes so you'll almost never find them on a boat trailer. You can get a larger axle with (larger) surge brakes just like those on the stock axle. You could stick with drum brakes, but the discs are about the same price so in my mind switching to discs on the new larger axle is a true no brainer.

[Simon]

Thanks Chip for that educated replie.

S

[crackles]

Thanks again Gents.

Chip, I misunderstood your different tire layout but still recommend you match all four when possible. What you should look for when using different tires of different axles is the Rolling-radius. If the tire on one axle is "bigger" or simply, higher, it will carry more weight than its counterpart on the other axle. I have seen tires blow when only one size out of step - albeit they were on a multi wheel low-loader. But I agree, for the boat trailer you should be ok for the time being.

I appreciate your help and enjoy reading your posts. Keep it up.

crackles.

[Hamin' X]

It is also important, that the hitch height is such that the weight is evenly distributed between thr axles(More difficult with different sizes). If it is off, then one set of tires is carrying more weight and will heat more and be more likely to fail. Also, the lighter axle will tend to scrub more in corners and make for some early and unusual tire wear.