Is it diff oil or just water?

[rodneybeauchamp]

Hi, refurbishing the RHR backing plate on 63 Riviera and thought I may have an oil leak at the gasket where it joins the axle housing. Had washed the plate with water and some detergent to remove brake dust, then used wet and dry rub with water to remove some surface rust.

When drying the plate with a clean rag, noticed a small fluid leak at bottom of axle plate, wiped with finger but unable to work out if oil or water, wiped again, still a small weep, gasket edge going dark and shiny ( moist). Fluid seemed clear and flowed easily ( like water does).

Tightened 4 retaining bolts just a tad ( technical term) and wiped entire plate and edge with a solvent twice. Left for 24 hours and seems dry ( as per photos).

Was the fluid just water from cleaning or is it diff oil is what I am unsure of. 63 Has the positive traction limited slip differential and don't know what colour the oil would be.

Have included photos of backing plate before I did anything as well as the same, 24 hours after my discovery.

[rodneybeauchamp]

And this photo too

[alini]

the axle seals are actually inside the axle tube and the axle bearing is behind the plate....its just water. 

Edited February 7, 2016 by alini (see edit history)

[smithbrother]

Catch a bit of it, then see if it will burn.

Dale in Indy

[64Rivvy]

just smell it - there is no mistaking diff oil for water.  it just plain stinks..

[rodneybeauchamp]

Many thanks for those sound words. After 48 hours, no sign of any fluid. When looking back, it flowed too easily for a heavy diff oil, had no colour and did not feel oily or sticky. So have repainted the plate and will keep a look out daily until the brakes are installed. It is great to have many heads together when you find a problem, certainly did not think of some of the responses that all made sense.