Overdrive Retrofit

So if I was going to add an overdrive to my '41 Zephyr, which would be less trouble - Columbia or Borg-Warner?

Since the VIN is stamped on the original transmission bell housing and the Borg-Warner overdrive requires a different transmission, you will lose your "matching numbers" if you use the B/W overdrive.

A Columbia axle will retain your matching numbers, if that's important to you. That's the main reason why I opted for the Columbia in my '41 Continental, even though I could have used the B/W OD transmission (or both!).

So if I was going to add an overdrive to my '41 Zephyr, which would be less trouble - Columbia or Borg-Warner?

The Warner is pretty complex and some of the bits are spendy (ask me how I know). But, it is essentially an automatic. Shift it into OD and forget it.

I like the way the BW OD drives, in second or high, take your foot off the gas at 22+ mph, and it shifts up. To me, its like a five speed. Second and OD is great for roads that need 25-35 mph or uphill without lugging the engine. My impressing is that overdrives are more plentiful, and therefore cheaper to obtain. You do need the shorter OD driveshaft and torque tube. I haven't found parts to be worse price than other manual transmissions I've messed with.

Abe

Thanks for your perspectives. I'll have to think on it. Phil, are you going to Santa Maria this weekend?

Sorry Dave, I can't make it this year.

My wife has had a stroke.

She is getting better but she isn't ready to travel yet and I can't leave her alone for a week.

So sorry to hear that, Phil. We all wish her a speedy recovery.

Dave