[Delicieuxz]

Originally Posted by welfare

I've been told syncromesh can eat at the brass syncros in these transmissions. Personally, I'd stick with Honda mtf. Especially if you're​ not intending to mask an issue and are just doing a service

Here's a quote I just found looking it up.

Before you guys jump off the bridge, I hope you realize the reason gear oils like Redline MTL, GM Synchromesh, NEO 7W (synthetic) and all the rest work so good is because they actually INCREASE friction, making the syncros 'crash' faster, with less grinding. It does this at the expense of synchro longevity, of course. This is not exactly news. However, many ppl consider this tradeoff to be well worth it. Just bear in mind that you aren't doing your tranny any favor by running any of these oils. You can't have it both ways. Less friction makes the synchros last longer, but you will get some 'grinding' when you shift. More friction makes the synchros work better, with less grinding, but it also makes them wear out faster...

If GM Synchromesh works better than anything else, and I'll have to take your word for it - having never used it, all that tells me is it's also the hardest on your synchros. Don't go into these blindly! It's a cruel world we live in, isn't it?