[Captain Slow]

Following on from another discussion, I thought I'd start a topic regarding diff failure.

I want to add a poll, but am unable to for some reason, so please answer this.

Has your diff failed?

A simple yes or no will do.

If so, have you...

A) Replaced like for like

B) Replaced with a Q2 due to failure

C) Replaced with Q2 for preventive measures

D) No failure, no action

E) Other

This should clarify the diff situation amongst owners. Please add model and age of car.

 

[Captain Slow]

I'll start.

My diff didn't fail, but gearbox did. I had a Q2 fitted as a preventive measure as the box was apart.

2002 156 GTA

 

[PANIC]

C

 

[Guest]

C: 147GTA, 05 plate car, diff replaced at about 20k miles/3 years old.

 

[AYAT]

156 Gta 2002, diff failed at about 50k with previous owner recon gearbox and diff replaced, bill £1800. Don't think q2 was around then but I upgraded when I bought the car. My sportwagon hadn't no failures but was replaced with q2 by previous owner at around 90000.

 

[bobda]

I've added a poll to the original post.

 

[Captain Slow]

Thanks!

 

[OperationAlfa]

2003 156 GTA, Diff failed and replaced with Q2 @ 64,000 miles

2003 147 GTA Diff failed and replaced with Q2 (by previous owner) @84,000 miles.

 

[aziraphale]

2003 156 GTA, owned for 3000miles, 108800mile car, option D for me!

 

[ducksonetime]

I installed a Q2 a couple of months ago. The inside of the diff housing was heavily marked suggesting the original diff had failed and was replaced like for like.

 

[badgers_nadgers]

D

2003 156 sportwagon. 50k miles, diff fine so far. Worried as hell, but feel I can better justify a gearbox repair to my wife (ie, the car's stuffed and needs fixing) than a six hundred + quid expenditure when nothing seems to be wrong.

I'd personally, be interested to know the relationship between diff failure and undertray removal/loss. Fwiw, my undertray is intact.

 

[aziraphale]

undertray? Wouldn't have thought it would have anything to do with it.....any theories?

my car does not have an undertray.

 

[badgers_nadgers]

I read somewhere on here that the undertray vents air over the gearbox to cool it and when the diff issue first kicked off it was in hot countries. For a time it seemed to be an oz only problem. I've just made the connection in my head and would be interested to know if there was a correlation. I could be completely wrong, but there seem to be an awful lot of people who don't think the undertray does very much and I just think that there must have been a reason they put one on. Could simply be a matter of aerodynamics and eu regulation as is often claimed, but the gearbox venting struck a chord with me.

For all I know the undertray doesn't even vent air over the gearbox and I've misread at some point. If it does, there'd have to be a good reason for it.

 

[Pud237]

The undertray does have a flap on it to direct air over the gearbox but I doubt it has any significant impact, if you've seen a broken diff up close you'd understand why - there just isn't enough metal for the load asked of it.

 

[Guest]

I had a Q2 fitted as my standard diff blew. Car is a 53 plate with 46,000 miles.

I went for a Q2 because of all of the good stories that I'd read, and it certainly helps traction.........but here's the rub for me:the Q2 hum (that virtually every car fitted with this diff makes) annoys me. In hindsight, I'd have gone for a standard diff because the car now covers less than 500 miles a year.
That said, I do believe that the Q2 adds value to the car, and would certainly make it more 'saleable' if I ever did sell up.

 

[alfabeat]

My diff went at 50,000, replaced like for like (and gearbox) as under warranty. At 90,000 put a Q2 in for preventative, but also just for the hell of it. It doesn't make a massive difference to me in terms of driving, and I have no noise from it at all.

 

[silvervalver]

YES - B

totally standard car which did 90% motorway work. Only 3 years old when it went with 28,000 miles! 147 GTA

 

[PR]

D for me, now at 109,000 miles. Original clutch aswell. May get a Q2 when the clutch finally goes however....

 

[Guest]

Mine came with a Q2 fitted, wouldn't have bothered myself as I don't think it's justified unless you track it. It does affect handling in power through corners though, noticeably less scrub out against my old 2.0 sele.

 

[LJ_GQV]

B. 2003 147 GTA, the diff went on mine last year at 28000 miles. Put a Q2 on as a replacement but was saving up to get it done anyway