yeah, when they get a bit of wear, a heavier oil will breath life into tired synchros. i think too, sometimes people just put in oil that is too thin and that causes a problem.

on my 82 240 with 250k it was wanting to graunch a bit so i drained it and put in 15w40 rotella. problem solved.

folks here recommend synthetic oil in stick trannies but i think often that is a mistake. the synchros are designed for a particular viscosity of oil and too thin makes them not work as well.

also giving it a moment between gears works wonders too. speed shifting works them unnecessarily.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.