93 SC300 5 speed
210k miles
I have been experiencing this issue with not being ale to downshift to 4th gear until I am at 40mph. I can force it, but it grinds, and slams into place. Similar feel to if you downshift to 1st gear from a considerable speed.

I am trying to figure out if this is an issue with the clutch or the transmission.

 

Bumping this post.

Since my post to start this thread, a lot has happened which resulted in replacing the engine and manual transmission.

My expectation was that the issue downshifting to 4th would go away.

Since the engine and tran was replaced. I find that the issue changed a little. Now i ave trouble downshifting to 3rd gear without a bit of a grind. Also i find that when accelerating from a stop, fast shift onto 3rd gear will grind unless I wait to shift when the RPM is below 2.5k (approximate)

Has anyone experienced something like this? Any guidance on where to look?