Triumph Repair: 1977 spitfire u joints, haynes manuals, infinite lack

Question
Hello Howard, I have two questions,

There is a muffled clicking coming from the rear when the car is driven. How can I tell if it is a u joint problem and if so which ones ie drive shaft or axle or if there is a problem in the differential.

I want to drain and fill the differencial. I can locate the fill plug  but can not locate the drain plug. How is it serviced?

Thanks, Pat

Answer
Hi Pat,

Yes, BLM in their infinite lack of wisdom removed the drain plugs. Normally you do not need to change differential oil as you can't ware oil out but you can contaminate it with metal filings  or even water. The only method you can use is to pump it out or remove the forward third member which often requires a new gasket. Note the transmission is the same way.

"U" joints can be looked at very closely for signs of rust and checked by hand and use of a pry bar to see if there is any free play. No free play is acceptable and any signs of rust at any part of the joint is a sign of a joint going bad.

You should purchase a service manual to know how to maintain the car. Haynes or Bentley make good manuals. Most auto parts stores handle Haynes manuals.

Howard