Fg Ute Axle Tramp

[Guest Slash]

Had some bilsteins fitted yesterday along with Lovells springs. Looks the goods, so hopefully it doesn't tramp it's ass off tomorrow night at the drags like usual!

[Ace]

I think I have had mine tramp twice since I owned it and both times were because it hit a bump as I nailed it

[Rancidpunx]

Its fairly easy to drive around it. Not sure about an auto though. Will only get it when nailing it and hitting bumps, just dont dump the clutch with more than 3500rpm, ie "launch control". Dont get it in the wet will just fish tail around.

[Smoke them tyres]

A good fix is to pull the springs out and have them reset in the opposite direction. This means that the spring will be fitted flipped over and leaf eyes will now go above the front pivot and through the centre of the rear shackle, rather than from under the bottom. This reduces the leverage the car and spring has on the shackle assy's and increases their curvature making them less prone to go into a large "s" shape under load. See how they deflect when following a car from the lights.

Also fit poly bushes to the eyes and if possible the saddle mounts where the diff sits. This will tighten up the "loose points".

Fit good dampers as already suggested.

My old used to suffer from axle tramp if you were too aggressive on the clutch. I did all this about 15 years ago, and have not had it axle tramp once since then.....no matter how I treat the clutch now.

Axle tramp bars:

-the ones underneath tend to be grass catchers and actually deform the spring under load. Less than optimal.

-the ones above the spring that fix their other end to the body (like the old standard XC GXL and ones) have a different body pivot point than the front of the leaf spring and result in suspension bind at large deflections. Not so bad with sloppy rubber that was fitted to them. This bind CAN RESULT IN NON LINEAR SUSPENSION CHARACTERISTICS AT HIGH SUSPENSION DEFLECTION. Read erratically tail happy. Also less than optimal.

Also, springs that have been lowered by lessening their arch to bugger all will suffer more from tramp as it's easier for them to 'wind up" and then release over and over.

The critical leaf in the "stack" is the second longest one. The critical part of it is how far it is from the shackle eyes. This can have a major impact on the stiffness of the stack. The also have plastic pads between each of the main springs at each end so they don't squeak and slide smoothly.

Another solution is to get some of the upper shocks of the quad shock 80's Mustangs. These lie horizontal and would dampen any sudden return twisting moments (compression).

Adding weight to make it slower??????......... :auto:

Edited 21/04/10 11:35 AM by Smoke them tyres

[Smoke them tyres]

The reset was done to my std Ford leaves.....no dramas in 15 years, so a reputable spring shop should be able to do it and re heat treat them.

[Gloo]

So...

Have the factory springs reset, but up side down.

Fit poly bushes

Fit good dampers

Ill get onto to a suspention shop and see what happens.

[Smoke them tyres]

That'll be the go

[mitch179]

I have an 09 manual, it's lowered an inch and has 20's, only seems to tramp if you are giving it the berries and you grab second and hit some bumps when breaking traction... only had it do it once with the DSC on, only once with it off too come to think of it.

I've only ever had it do it on bumps, that's what seems to upset it?

I also expected it to be more taily than it is, in the wet it's border line scary but in the dry it doesn't seem to spit sideways as easy as I was expecting!

Regardless of the quirks I love my ute

[wogrocket]

I got a BA pursuit and it did tramp as its lowered but I have solved teh problem by making up 2 straps to hold the front of the leaf springs togeaher cost of about $5 and about 30min to do and works a treat... I'll post some pics up later

Mick

[riki83]

There seems to be alot of utes with this in the FG models bar the fortunate few of us.

I now have 33,000 on the clock and havent experienced once. Rears sit up in the guard

on 20's and still everything is sweet. Its been way overloaded a few times, 950 kg 6 times

or the usuall week day drive load of 3-400. It gets a hard time a fair bit and since 10,000

runs 340rwkw. I get it back on wednesday hopefully round the 400 mark but seem to mainly

be the manuals with this problem.