Triumph Repair: Reverse on 1978 Spitfire, forward gears, hub carriers

Question
Jim,
I have a 1978 Spitfire with 56,000 that has just begun to jump out
of reverse. It won't even stay when I push and hold the gearshift
lever. FYI, I have had trouble with the trans occasionally jumping
out of 1st gear and going down hill in 3rd gear. Last year I had a
new overdrive solenoid installed by a shop.
Thoughts?
Tom

Answer
Tom,

Usually when the Spitfire trans starts popping out of gear in the forward gears it means that either the synchros are going, or the spring loaded detents on the hub carriers are going.

As you're having trouble with reverse also it points to possible problems with the roller bearings that support the laygear.

In any case it sounds like the trans is due for an overhaul.


Cheers,

Jim