The transmission is one of the most common parts to fail on a vehicle. Unfortunately, most failures can be expensive – the going rate for a brand-new transmission ranges from $4,000 to $8,000, according to Angie's List. It's little wonder that a used transmission from your local used auto parts shop is often a better deal.
Seeing is Believing
Being a sealed unit, it can be hard to properly inspect a used transmission without taking it apart by hand. Fortunately, there are a few things you can do to confirm if it's worth buying:
- Check the dipstick – A good way to check the transmission's condition is by sampling its oil. Healthy transmission fluid is often bright red in color, while bad transmission fluid is often brownish or an extremely dark cherry red. Burnt odors and metal flakes should immediately send up red flags.
- Crack open the oil pan – It's a good idea to remove the transmission oil pan and take a look inside. Check for accumulations of metal flakes and fragments on the transmission's magnet. Also make sure there aren't any signs of damage or wear on any visible components.
- Beware of rust – If there's a significant amount of surface rust on the transmission, there's a good chance that it's been outside exposed to the elements for quite a while. It's also a tell-tale sign that the transmission itself might be junk. Excessive rust can also wreak havoc on shift linkages and, in some cases, even penetrate components inside the transmission case.
- Spin the input shaft – Carefully turning the transmission's input shaft by hand (or with pliers) can tell you whether or not the transmission has seized.
To Install is Human, but to Rebuild is Divine
It's not out of the ordinary to directly swap a transmission from a salvaged vehicle to another running vehicle. However, there's also a good chance that the transmission of your choice requires a little work before being put back into service.
This is why it's often better to purchase a transmission with the intention of rebuilding it. The rebuilding process gives you an opportunity to refresh worn-out components and inspect the internals for signs of damage or defect – something you wouldn't be able to do during a direct swap.
What About a Warranty?
Most used auto parts shops and salvage yards offer a short warranty for used transmissions. Some warranties last for 30 days or more, while others last only 5 days. It's also not out of the ordinary for transmissions to come without any sort of warranty.
Before you make your purchase, you should find out whether your transmission comes with a warranty. If it doesn't, it may be possible for you to negotiate one or at least ask for some time to have the transmission checked out by a professional. For more information, contact a company like Karr Parts.