Diff problems?

[JonFD]

Hi guys,

So im 99% sure its the diff. but just want some other opinions, and a way to check.

I did a slightly spirited take off at the lights earlier, to be greeted with a nice tapping/clonking sound from the rear.

The noise only happens under load, got about 3 miles without it making a sound cruising at low revs.

Broken diff? I've had a quick look and there's nothing wrong on the shafts or hub areas.
Is there a way to really check it? drives fine in reverse and apart form the noise actually dives fine all over lol.
I gave it a decent bit of throttle near home (mainly to see if anything worse happened) and it just makes the noise at a faster rate with engine speed...

Its really annoying, the only problems I have with this car are all suspension and drivetrain, so far...

 

[Paulm]

Ppf?

 

[Nas80]

Diff bushes. They are fluid filled and they basically die after a while.

Get poly ones as theres no difference with vibration..

 

[Nas80]

There's you go straight swap

https://fdoc.co.uk/forum/threads/diff-carrier.1921/

 

[JonFD]

Did the diff bushes the first month I had the car lol...
was thinking I'd snapped the hanger at first but that seems ok - and I doubt I'd have got this far now.

It's like a broke gear type knock/grind, and only happens under load or boost, I just managed a trip back to work without it doing anything.

I'm gonna head back home now, any idea what I can do to check, as it behaves itself going slow I doubt I'll re produce it jacked up by hand...

 

[JonFD]

Ppf?

God hope not, wouldn't I be getting all sorts of noises the whole time? It wasn't dramatic when it happened, I just heard it go all clonky

 

[Paulm]

God hope not, wouldn't I be getting all sorts of noises the whole time? It wasn't dramatic when it happened, I just heard it go all clonky

When mine went it would clonk / click as it went on / off boost

 

[Ceylon]

Doesn't sound like diff to me. Any vibration?

 

[JonFD]

Fair enough, where about did your ppf break or whatever? getting abit dark now and so pointers would help lol.

@Ceylon - could it be shafts or cv's? Im gonna go jack it up and see if theres any play or anything more obvious.

Just to add, lifting the hand break slightly to simulate load makes it click, and it does sound like its right behind me, can almost feel it in the floor.

 

[JonFD]

When mine went it would clonk / click as it went on / off boost

Did yours make constant noise? its constant and speed related on boost, nothing on decel etc and no clonk, its more a grind. I think its deffo a moving part of the drivetrain....

 

[Nas80]

Are you getting wheel hop?

 

[JonFD]

Are you getting wheel hop?

Well, yes and no, much less now with the bushes n pillow balls done, but it still does if it just looses traction. I did engine and diff mounts first to try, and they did help...

 

[JonFD]

But....

@Paulm was bang on the money.. Give that man a cigar lol....

Nice crack in the PPF...

How tho? do they just go? Id a;ways bank on a moving part going, not a solid bar....

I did have a new clutch put in, and after seeing that thread about PPF alignment, (I know my guy did not know about this) I'm wondering if that could have lead to it or am I being paranoid lol?

 

[JonFD]

This isn't weldable is it? too precise and under load to try?

 

[Paulm]

The clunking under load after a hard pull made me think ppf. Its what broke mine
Plus whenever ive done a diff it whines like my wife

 

[Ceylon]

That'll weld up fine .

 

[Paulm]

Will mig cut it or does it need tiging? (I aint fixed mine yet)

 

[Ceylon]

Mig will be fine. I'd strengthen the rest while you've got the welder out, look at the Japanese aftermarket ones for some ideas of where to seam weld and brace .

 

[JonFD]

Mig will be fine. I'd strengthen the rest while you've got the welder out, look at the Japanese aftermarket ones for some ideas of where to seam weld and brace .

Nice, saves some dosh at least. I've had a look but can only see find home made ones or mazdaspeed.. care to name some brands?

In terms of the alignment etc can I just whack it off and back in on the street with a jack and stands or will I need a ramp for it.

And I thought I was just needing a front mount doh!

 

[Paulm]

Mig will be fine. I'd strengthen the rest while you've got the welder out, look at the Japanese aftermarket ones for some ideas of where to seam weld and brace .

Thanks for the advice, I'm already not looking forward to doing this