transmission on 78 124 spider

[lesholmes]

The only problem I seem to have is the gear changing into Reverse has become harder over the last couple of years, feels and sounds like metal on metal trying to drop into reverse. any thoughts with-out dropping the tranny. Homer

[klweimer]

Homer,
Short of dropping the transmission, I think your only option is changing the oil and hoping that helps for a while. Lots of opinions on the forum as to what to use, but your typical 90W gear oil they want to sell you at the parts store or Jiffy Lube is not what you want. That's because the additives in the oil will break down the "yellow metal" (brass) synchronizer rings. You need either a GL1 mineral oil or a synthetic made for these transmissions.
https://www.amazon.com/gp/product/B000C ... UTF8&psc=1
https://www.amazon.com/gp/product/B00HF ... UTF8&psc=1
I used the Redline and have been very happy with the results. Do a search on the forum for changing the oil in your transmission, as there are lots of good ideas and tips here.
Kirk

[bulldog4444]

What I found with my spider over the past 35 years was that when I put it in reverse I too heard and felt a metallic clunking noise. A number of years ago I tried an experiment by first putting the shifter in third gear, then into reverse. No more noise or metallic clunk.

What I think is happening is that the clutch is not fully disengaged even though you have the peddle fully depressed. So when you select reverse, bang, metallic clashing. I can slightly hear this rotation but if I engage third gear before going to reverse, it stops the rotation. This is my experience, let me know if it helps.

[RRoller123]

Same here, stops the gnashing.

[superbenk]

As for transmission oil, if you have a Tractor Supply nearby check out their Traveller SAE 90 tractor oil. It's 100% GL1 mineral oil which is what's called for in these transmissions. Just picked up a 2 gallon jug for $18.