Which Diff Bushes To Replace In Fg F6?

[Jackson93]

Looking to replace diff bushes, feels really clunky in the rear end when I hit high revs and shift too quickly.

I've read mixed reports of the nylon bushes and I've also read some good reviews of the "super pro" diff bushes, would like to know where to purchase as well.

Also how hard are they to replace (my brothers is a heavy diesel mechanic), is it hard to stuff it up?

And last of all, am I doing damage to my car by letting this go on?

Thanks for reading!

[Jackson93]

I will be checking in regularly for the next few days, so all responses are welcome.

[FormulaFG]

A few questions for you,

how hard do you drive the car and how do you feel about noise and vibration?

Sounds like you drive it like its meant to be driven so you might consider going onto Australian Ford Forums and getting in touch with a guy called Daniel, goes by the username CAT600. He can suply you with a pair of his front diff bushes. He also recommends using them with the Nolathane rear diff bush.

Super pro diff bushes are quite good too. The comfort series (the ones that look like a turbo compressor wheel) replicate the factory feel most closely that a urethane bush can. However they can tear more easily due to being softer and having the voids in them.

Ebay is probably the cheapest place to get any of the above bushes, excpet the CAT600 ones.

Its a fairly big job to replace the diff bushes because the whole diff cradle needs to be dropped out. If youve got access to a hoist that makes life a lot easier.

If you let this problem go for too long you will damage the bolt that holds the rear bush in or you can run the risk of wrecking the thread that the bolt goes into on the diff hat.

One more thing to consider is that your diff centre might have some backlash and it may not be the diff bushes alone that are the problem.

[aiboart]

Suspension Compliance is not a dirty work.

Compliance = Grip.

Ive fitted whitline bars front and rear

Sway bars kill suspension compliance and therefore reduce grip. That is how swaybars are used in suspension tuning.

Even on dead flat roads

Fitted to the rear swaybars allow the back of the car to slip more in order to increase vehicle rotation around the front wheels.

Fitted to the front swaybars allow the front to slip at the front therefore reducing vehicle rotation around the rear wheels.

Fitted at both ends... swaybars allow both ends to slip.

On bumpy roads - in addition to the above -

By fitting a swaybar you have reduced the ability of the suspension to move in response to variations in the ground. The car has less grip and what grip you have is poorly distributed from moment to moment - which causes the vehicle to wander.

the previous owner fitted bilstein shocks front and rear

The Bilsteins will improve grip and compliance... and make the car feel stiffer.

How?

At crawl speed the all suspension movements are at low velocities, so yeah, the Bilsteins reduce grip, but, the amount of grip you need at 20kph is trivial so it does not really matter.

Once up to moderate driving speed the suspension velocities split into two groups.

The high-speed suspension movement results from impact with bumps - this in turn pops the relieve valves in the Bilsteins making the suspension softer and gripper. Compliance is grip.

At moderate driving speed and above, low velocity suspension movement corresponds to body movement only; the Bilsteins remain hard, thereby providing rapid chassis response to steering and other driver inputs.

and rear and urethane bushes in the front

If your suspension is already as ridged as too steel, by fitting hard bushes you have further reduced the ability of the suspension to move in response to variations in the ground.

The car has less grip and what grip you have is poorly distributed from moment to moment - which causes the vehicle to wander.

Some more points -

You need compliance somewhere in the suspension. If you reduce compliance in one area of the suspension then another part of the system may be able to cover. It is therefore possible to have hard springs or bushes or whatever... but, making everything ridged is simply not going to work ever.

Check your springs. They may be 'upgraded'... . What you need is factory spring rates.

The tyres are a critical part of the suspension system.

Removing sidewall flex is feasible, but in complex conditions, it results in reduced grip.

On smooth roads reducing sidewall flex and making the tyre wider can add more grip, but, the grip gained is subject to brittle failure. Rather than having a nice progressive breakaway as you would have a slightly narrower and higher tyre, the ultra low profile wide roller tyre will provide uber grip right... until the instant in time that it provides no grip at all......

In short, if you are running 20" rims and rubber bands go back to factory spec wheels and get some high end tyres.