Rear trailing arm bushes....RTAB Powerflex

[dva99999]

I’m considering adding polybushes to the rear trailing arms of my 2.8, due to a bodge job by a local mechanic who didn’t fit the drivers side standard bush correctly . (No point in naming because I’d never normally go to him.)

As I’ve already fitted rear crossmember polybushes but kept the diff mount as standard (also have powerflex rear ARBs) has anyone had this set up fitted and did it improve handling while reducing any rear end stresses?

I ask because as in a previous post I found that having the polybushed diff mount fitted I didn’t take into account that the crossmember and/or rear trailing arm were just rubber. This meant the boot floor and subframe chassis started to say bye bye to each other due possibly to all the stress being transferred to the diff mount. I’ve fixed that issue now, I still have the polybush diff mount and awaiting someone competent enough to press in the standard rubber one.

I’ve read #mikefishwicks post about subtle stiffening but haven’t seen anything about this set up

Currently have:
Powerflex rear ARB’S bushes
Powerflex rear crossmember bushes
standard diff mount bush

Looking at :
Powerflex rear trailing arms.
Putting the Powerflex diff mount bush back on???

Any thoughts?

 

[t-tony]

TBH, I think many people fit the power flex bush in the Diff. mount simply because it can be done without removing the Diff. rear casing and losing the oil. Consider how long the original rubber bushes have lasted and think how long you need them to last for normal road use.

Tony.

 

[dva99999]

It was the diff mount bush that caused this problem, although the crossmember and rear trailing arms had standard rubber.

 

[t-tony]

It was the diff mount bush that caused this problem, although the crossmember and rear trailing arms had standard rubber.

View attachment 169467

I wasn’t disputing that for a minute. I was simply saying that people can be lazy and tight fisted and go for the cheaper/easier option, you were unlucky that the previous owner of your car went that route (also ripping the floor apart like that comes from having had a very hard life).

Tony.

 

[dva99999]

I wasn’t disputing that for a minute. I was simply saying that people can be lazy and tight fisted and go for the cheaper/easier option, you were unlucky that the previous owner of your car went that route (also ripping the floor apart like that comes from having had a very hard life).

Tony.

I have to say.....it was me that fitted it . I only noticed the problem after driving 200 miles, by which point there was that rhythmic noise of something catching under the rear of the car. To be fair (to myself at least) I did fit it some 3 years ago. When I inspected the car prior to buying it, there were a couple of rust spots in the boot where the spot welds were. That was over 5 years so it’s possible that the problem was there and I just exacerbated the problem by fitting the harder diff mount bush.

 

[gookah]

I fitted poly bushes all around, beam, diff and trailing arms..
two weeks later:




The diff bracket snapped completely,
It looked like it had been broken on one side for a while (darker colour,) but the extra stresses finished it off.

Diff bracket has been welded and strengthened, but I will be taking the whole lot out again this year and replacing with standard bushes.
The car now feels every bump and hollow and creaks from all over the place as it shakes things apart.
Great at handling, but getting a bit tiresome now.

 

[dva99999]

I fitted poly bushes all around, beam, diff and trailing arms..
two weeks later:
View attachment 169469

View attachment 169471

The diff bracket snapped completely,
It looked like it had been broken on one side for a while (darker colour,) but the extra stresses finished it off.

Diff bracket has been welded and strengthened, but I will be taking the whole lot out again this year and replacing with standard bushes.
The car now feels every bump and hollow and creaks from all over the place as it shakes things apart.
Great at handling, but getting a bit tiresome now.

Ouch!!!

 

[gookah]

wasn't fun limping to a nearby Homebase with the diff dragging on the road, I was 20 miles from home at the time, managed to jack it up and chain it up to get me home:


You can see how the back cover had worn away, even partway up the drain plug

 

[dva99999]

wasn't fun limping to a nearby Homebase with the diff dragging on the road, I was 20 miles from home at the time, managed to jack it up and chain it up to get me home:

View attachment 169481
You can see how the back cover had worn away, even partway up the drain plug

What effect did that have on the drive shaft and the diff itself due to the angle?

 

[gookah]

Have had no trouble, so no lasting effects and that was 4 years ago, it was only for about half a mile, very slowly.

 

[dva99999]

Have had no trouble, so no lasting effects and that was 4 years ago, it was only for about half a mile, very slowly.

I will put the standard differential bush back on as it will allow a small amount of movement with no stress to the mount. I’ve also strengthened the boot floor using a combination of a Randy Forbes inspired welded kit, aviation sealant from Airbus and doubling up by welding new plates on the existing mount holder.

 

[dva99999]

I’m also getting primer and paint for the boot floor which will harden once dried.

 

[Deleted member 15689]

Poly bush does not cause this .it must have been rotten to start with

 

[gookah]

Which is why I said the poly bush probably finished it off.

 

[Nodzed]

people can be lazy and tight fisted and go for the cheaper/easier option,

EXCUSE ME! My zed, as are a lot of other owners Zeds, is fully poly bushed, wasn't due to laziness or being tight...... OEM bushes are cheaper than decent Poly bushes!

 

[t-tony]

With regardS to time taken to remove the Diff casing (to fit a new standard bush) and refill with new oil and paying someone to do it for you, compared to the cost of fitting a poly bush only I would beg to differ.

Tony.

 

[dva99999]

With regardS to time taken to remove the Diff casing (to fit a new standard bush) and refill with new oil and paying someone to do it for you, compared to the cost of fitting a poly bush only I would beg to differ.

Tony.

Well I am lazy....I want to do job but in as little time as possible.
I am tight fisted....I can’t afford to pay the going rate for a mechanic to do it and rip me off.

 

[t-tony]

Well I am lazy....I want to do job but in as little time as possible.
I am tight fisted....I can’t afford to pay the going rate for a mechanic to do it and rip me off.

That was the only point I was raising.

Tony.

 

[Nodzed]

With regardS to time taken to remove the Diff casing (to fit a new standard bush) and refill with new oil and paying someone to do it for you, compared to the cost of fitting a poly bush only I would beg to differ.

Tony.

It's also about performance and longevity.

 

[Nodzed]

That was the only point I was raising.

Tony.

Well sorry but it's a bad point. I have certainly not been tight fisted in maintaining my zeds the proof of that is on here and neither have a lot of others but nearly taken the route of preference and yes maybe ease. As the Zedshed has done a lot of the big jobs on my Zeds you may say lazy but I have gone with knowledge and expertise.