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Let's go to this side, over here, where we can have a couple of moments to talk about the actual Trailing Arm and the differences between the wet and dry ones. In this case over here, our customer had a Hydrolastic Suspension-Wet Suspension Mini and he's changing it over to a complete Dry Subframe with Coil Springs.

So in this case we're using the Dry Rear Arms along with. The differences are, when you look at them, this Brake Hose was attached to the top of the Arm with the dry Cars like this. Right now we have it upside down, again, remember when you look at a Wet Trailing Arm compared to a Dry Arm this Bracket's on the other end is using a different Metal Hose to the Rear Wheel Cylinder.

But the more important difference and it's very subtle-I don't have one to compare- the Spring Rate is a little bit different. That was done to make the Hydrolastic side work, it's perfectly fine to use a Hydro Arm in a dry set up because you're just talkin' Coil Spring, you can adjust the Ride Height. But for the Wet type this was revised slightly, so the car had a level attitude.

What happens with Mini's in general is, the back is so light that they tend to have a" jacked up" in the rear look, when they didn't make an adjustment here to the rate allowed by this Casting. You move it from center line, you change the leverage and they optimized it for the Hydro-both work. In this case this is a complete Dry Set Up.

Let's take a quick look here at the order of assembly here. This is, kind of, the Camber Plate item. These are sold with Adjustable Camber Plates. This is a standard one; bolts right here, but you cannot install this with this in place.

I'm going to show what you go through to rebuild these Arms. In this case the Bearings are installed, the Bushings installed, here's the Shaft tube, you've got a Zerk fitting over here. One quick thing -these are provided with a Plastic Insert, that's already inside here, but this is what it looks like. This comes in the Kit, people ask "what's that for?" It protects the inside and provides somewhere for the Grease to be captured and forced to the outside. So you're not filling this whole Casting with Grease. That's in there.

We've got our Zerk properly arranged. The way to remember this is, your Shock Pin-of course has to be on the inside, your actual Stub Axle will have to be on the outside. It's possible to put them in backwards then you're looking at it going -geez, where's the Hub going to go. But in this case- Zerk outward, the Bushings on the outside, the Roller Bearings on the inside.

Again, this is upside down, so this Joint Knuckle area is going to be at the top. Basically there's the Arm assembled, installed. We can slip it into here. There are these special Thrust Washers. In this case, I put the little Seal around the Thrust Washer with the groove in it. That groove goes against here, because that's designed to carry Grease. So to put that in place, you can simply slip that into its hole. It's a relatively tight fit so I've got a soft hammer here to keep the arm in place.

When you look at the Thrust Washer, we pointed out how there's a groove in it. That's for Grease which is going to be fed under pressure through the Zerk from the inside of the Shaft out into the Bushing and the Bearing. So the order would be- that groove goes inward to pick up the Grease and provide lubrication as the Swing Arm moves up and down with Suspension travel.

So we got the Thrust Washer in place, this weird little O Ring just basically goes around it and provides a weather seal. You should be able to hold it in place feed it over the Thrust Washer and have it engage, basically, right over there. When the side plates in place, it just acts as a water, whether, debris seal.

Then the Camber Plate is installable, it's going to grab the Axle as you line it up. Of course the paint on these has made them a very tight fit. But essentially that's what holds the swing arm in place and you have to put it together in this order. Let me put one bolt in here to hold it.

Again and we're illustrating the order of assembly here. We're not too worried about tightening everything up. Obviously that would be done later, but now this arm is going to be in place you've got a pivot here you've got a pivot there.

OK, so just one quick little thing to show here, from a lot of experience working on these. The Mini's not a difficult car to work on, but while you have this Arm loose, before you put the Spring on and restrict the motion, look around at what you can do. For example this Brake Hose, it's not too horrible to have to reach in here and bend it but if you lift the arm up, you can slip right into the hole where it has to go in the Subframe.

Now that's located we just need to start the Nuts over here we're ready to install the metal line when it goes into the car. So let's show one more time, I've got the Hose in place here- let me put the springs in with the Hi-Lo, with the Trumpet piece, basically making it engage a little threadless Stud that makes up the Joint Knuckle. That puts the motion of the Suspension such, that we can slip the Spring in place.

Let the weight of it down- everything pops into the place. We've got our Brake Hose assembled through the hole ready for the Nut on this side. Let's have a quick look at our Backing Plate now. We've started a couple of Screws here, we started the Bolts here, everything's held in place.

We'll sneak this into the triangular mount here and we put the Nylocs in the back, that locates the Brakes and that's pretty much the whole assembly. Of course- hardware and stuff to be installed on the back of here, tightening all these up.

Again remembering it's upside down, everything's self supported -this is basically the complete Sub frame, when you're done with all the hardware. So your Parking Brake Cable's going to come from the Handbrake through that Bracket, right through here, around this Lever and go over to the Arm.

So you can see how, with the assembly correct, there is the Arm for the Parking Brake- at the top. You can see the Cable path very clearly. If you put this together and something doesn't line up, somethings backward.

Remember you're going to flip it over. At that point you would have to support this. With the Coil Spring you'd need to keep this from flopping away, as you turn it over. You can hold it in place, somehow, for ease of assembly, get it in the car, get your Shock Absorber in place. Now nothing can fall out.

When you could buy this, it was a Stock Mark IV, with Rubber Springs and everything that came on a '76 and later Mini. In this case we're changing one out for a Hydrolastic, so you can look at it that way. There's actual benefits to us assembling a Custom Frame for exactly what you're doing. You can order the complete part, ready to bolt on or you can order any of these pieces individually.

We can use you're Subframe, detail it out, however you want. It's a very nice way to really address the complete rear end of the car, a nice simple setup that's worked for five and a half million Minis.

Please see the next Video-Article: How-To Upgrade to a Hi-Lo Suspension in your Classic Mini No 1