Assessing differential condition

[simonej]

I've just bought a scrapped differential with a view to replacing the groaning and moaning one that's currently strapped to my car. (The idea being that if it needs a refurb I can get it done whilst the other one is in the car and therefore minimise the time that car is off the road - if that makes sense?)

Anyway, I have no idea what condition the diff I've just bought is in other than that with the cover plate removed it looks like this;



I fully expect to be told that the only way to be sure of the condition of a differential is to have it refurbished but this seems to move smoothly with very little slack, just a fraction of play when turning the input. There were no iron filings in the oil and it all looks pretty sharp in there. One question though, both outputs will only turn at the same rate (they feel locked), should I be able to move them at different speeds by hand or is that beyond the force I'd be able to generate?

As you can probably tell, I'm not using any technical terms here so probably best to assume you're dealing with an idiot! Any help greatly appreciated.

[CarlosV8]

I bought a spare diff for my Chimaera, with the intention of getting if refurb'd prior to fitting. When I picked it up it all felt quite tight - certainly less slack than the one on the car. I toyed with the idea of just bolting it in and hoping for the best, but decided to shell out and get it done so I didn't have to worry about it again. Grantura Engineering did the work (great service BTW) and came back saying the bearings were completely knackered. Glad I didn't fit it and goes to show you never can tell if you don't know exactly what you're looking at (although I didn't bother checking the internals like you have).

The diff is still sat in the garage waiting to be fitted, but with the current diff sounding worse and worse I'm glad to know the one going in will be spot on, with nothing to worry about. Peace of mind is a nice feeling

[simonej]

Thanks Carlos, I think getting it refurbished is the best way to save myself a lot of hassle and is indeed what I've been advised by professionals. I'll start looking for somewhere to send it...

[CarlosV8]

I phoned / emailed a lot of companies for both refurbs and 2nd hand units, but the best IMHO, in terms of customer service, price and reputation was Grantura. Well worth a call!

[haircutmike]

for Grantura, had mine back within a week!