Yes I think that this will help I would also check the travel for the clutch and see if there is room for minor adjustment. Also check selection alignment as this may also be slightly out. Had similar problem with my Tr and did all of the above, especially no. 1 and it helped a lot. regards tony
Is it only when its cold ? I find those synchros to fail often, especially 2 & 3 probably bcus they are the most used
There is no clutch adjustment, but it may need bleeding. More likely though is a clutch/spigot bearing dragging so rule that out first. A dragging clutch can highlight a weak synchro problem. Get the rear wheels off the ground and select any gear with the handbrake off and engine running....make sure the wheel dont turn while your foot is on the clutch. But in summary...yes, good oil will make a difference to a TR...there's about 7.5 litres of oil in the transaxle which is more than most cars have in their engine. Make sure the oil you use is a HYPOID oil, and not just a HELICAL. You'll kill your pinion with a helical oil.
Good stuff... http://www.mobil.com/USA-English/Lubes/PDS/GLXXENPVLMOMobil1_Synthetic_Gear_Lubricant_LS_75W-90.asp Rgds, Vince