Morris Minor Owners Club

My 1970 Traveller's standard rib-case gearbox crunches when going from 4th to 3rd gear. Is there any way of freeing off the sticky synchromesh, perhaps with an oil additive or different grade of oil (it currently has the usual 20W50 Halfords Classic engine oil in it)?

At the moment, I try to double-declutch when going down from 4th, or avoid 3rd and go for 2nd if say turning off at a junction, but there's not always time to avoid the dreaded crunch!

That's what happened to my A30 box some years back, lived with it for a while but eventually sent it to John Evans who sorted it out at sensible money. It's been great since.

I bought my 1969 tourer some ten years ago knowing that it "crunched" when changing through third gear. I used to double declutch each time both up and down the box until I bit the bullet and rebuilt the box last January. The synchromesh in third had worn and now with all the relevant bits and bobs now changed with brand new she's as smooth through all gears as if she was new.