I bought some RedLine Synthetic gear oil a while ago and was toying around with the idea of putting it in my transaxle. A little hesitant
Any Pros or Cons?

the bad news: everyone on here has said not to use synthetic gear oil (do a search and you will find many threads on this topic)

the good news: i just saved a bunch of money on my car insurance

Click on the 31 pages of notes link below and read up on it.

Use DINO oil...its cheap and it wont wear out the syncros.

Rich

I tried it a long time ago. Don't do it. It's too slippery for our 1950's design synchros. Swepco 201 works great. Cheap shit seems to work OK too, but I feel better about spending more on Swepco than I do about putting Walmart's cheapest in my very expensive transmission.

Thanks guys, and Doc. I'll read your notes.
I f-ed up a perfectly good flat tappet engine by running Synthetic oil, still not fully sold on the stuff.

The short summary, dino oil lasted 30+ years in the box, if you think synth will improve on this, with out any proof, may the force be with you

I'm good, Swepco 201 is what I always used, I'll keep it that way.

redline in my tranny, when i bought the car if shifted poorly very poorly, changed oil with new dino (stalube) no improvement, then put in redline synthetic, and it shifted great, now over 80K miles later, it still is fine, that redline is good stuff, jucst be sure you buy the redline with the correct additive package for our transaxles 9they make a specific blend for us) I forget the exact name of the product (they have changed the naems over the years) selection of the correct redline product is esential.

I could hardly believe the mechanic in the drum worked so well on my hard shifting tranny, but it worked, have since used it in my van and Bug trannys, friend uses redline in his tranny too,
it is a good product.

I've run synthetic in my 914 tranny since 1994. Since Mobil-1 doesn't use an EP package that I trust anymore I like LE (Lubrication Engineers). I use synthetic because I'm pushing a lot of torque into it and I want to save the R&P. 7:31 is very aggressive for a small diameter ring like ours. It makes for highly stressed pinion teeth. My maintenance history in a nutshell...

- I have replaced one synchro (last year) but only because I had one that was a little better, not because it was worn out.
- The R&P teeth were just fine.
- Dogs were pristine as well

That said there are a few things that you MUST do in your shifting style. Technically these are also true with dino oil, but you can wear out your synchros/spiders/sliders if you don't do the following rigorously.

1. At the bare minimum, match engine revs before shifting up or down.
2. NO SPEED-SHIFTING
3. Double-clutching is the the best... period.
4. Always push the clutch all the way in when shifting in either direction.
5. Keep the clutch adjusted properly.
6. Keep your trans fluid-level correct.
7. Save aggressive shifting for when the trans is warmed up. On the street with synthetic fluid mine stays around 150 - 170 F after a few miles. When the temp goes much over 180, like on the track, it's time to turn on the pump and shove it through a cooler/filter system.

If you aren't willing to use discipline with these transaxles then stick with dino oil. In either case, smooth is good... very good.

Good luck