Hey Duke here and just in case your wondering what we are going to bark about today........It's the Transfer Case.  

Ever wonder how all-wheel-drive or 4-wheel-drive vehicles get the power from the engine to the front and rear wheels? The magic happens in what's called a transfer case.  In some all-wheel-drive vehicles, it's sometimes called a power take-off unit or PTU.

Inside the transfer case is a set of gears.  To keep those gears meshing smoothly, they must be lubricated and kept cool.  What kind of fluid does my vehicle use? Depending on your vehicle's type of transfer case, it is filled with either an automatic transmission fluid, a gear oil that's a bit thicker, or a transfer case fluid designed to be used for your transfer case.

As with all lubricating fluids, the transfer case fluid has things that break down the older they get.  They have corrosion inhibitors, detergents, and anti-foaming agents that keep the lubricant from getting air bubbles in it. Transfer cases don't have filters in them to clean out impurities.

If you don't have your transfer case fluid exchanged for fresh, you risk damage to the case, and that can run into thousands of dollars.  So the wise driver makes sure the fluid is changed according to the manufacturer's recommendations.  For many vehicles, that is every 30,000 mi/50,000 km, but some require it more frequently.   Your vehicle service facility can advise you on what your vehicle's optimal interval is.

During the fluid exchange, any metal filings that may have come off are cleaned off the drain and fill plugs that are usually magnetized to catch the stray metal pieces.

If you hear grinding noises coming from under your vehicle or if it is having trouble shifting gears or going in and out of 4-wheel-drive, those could be signs your transfer case needs service. In that case, have our technicians check it out.  The best plan of action?  Keep your transfer case fluid maintained and it should keep you heading down the road for years to come.

Now in case you are wondering who invented the 1st automatic transmission here it is:  

Allied Auto Works
2073 Grant Road
Los Altos, CA 94024
650.968.7227
https://www.alliedautoworks.com/