My Quaife 5-speed came filled with Shockproof, which was okay. I switched it out for Mobil 1 GL5 and have been happy with the results. Shifts are smooth, cold or hot, and it seems to stand up to quite a bit of abuse.

An update:

Motocraft XT-M5-QS is friggin awesome. Now I understand why they charge $25 a bottle for it- this stuff has to be at least 50% unicorn milk by volume.

Upon draining the transmission, a shocking amount of metal came out of it. Aside from the usual metal dust, there were a couple of pieces of what appeared to be spring steel, the longest of which was about 1cm, which I surmise must be the remains part of the second-gear synchro apparatus.

Despite this, the transmission now shifts like it was new. The 1-2 gearchange is smooth and easy under all conditions, with no double-clutching necessary. I have heard a few folks say that it takes time for this lube to do its job, but the improvement here was total and immediate. The very first drive after the oil change evidenced a complete remission of the difficult gearchange.

Highly recommended.

Winning! I'm glad it worked out for you :bigtu:

Back in the day with I tried the Motorcraft in my 5 speed I had the hardest time convincing the guy at the Ford dealer to sell me the stuff. I can *kinda* understand why, because the T5 5 speed manual in the fox body Mustang takes ATF rather than gear oil... :rofl:

After a lot of soul-searching, I put Motorcraft Unicorn Tears in my replacement Quaife tranny. So far, I'm very pleased - shift action is light and precise. Once I begin track days again in the spring, I'll let you know if I'm still pleased.

Amsoil 75w-90 for me. A little finnicky when cold but you just need to be more positive with your shifts.

Honestly, the MiataRoadster shifter is what improved shifting for me altogether. Before I said so much play in my shifter I always missed 3rd/4th.

That in conjunction with Amsoil makes a nice snick-snick shift with zero syncro bind, grinding, or problems, even in 40* weather.

I've always had a problem with 2-3rd hard shifts with some pretty bad grinding even when being very firm with the shifter and attentive foot work. Previous fluid was unknown, had valvoline 75w90 in this season, wasn't any better. However, shifter feel has always been nice and smooth. I did change to a Ralco shifter after having a bit of an incident with the stock shifter and it feels really satisfying. Shock proof was mentioned earlier to help the problem. Has anyone else had the same problem going on?

The parts guy at my local Ford dealer just made some smartass remark about selling me Ford parts for my Miata like I didn't know what I was doing.

Glad it worked out for you Joe. $25 a bottle is way too much though, believe the local dealer had it for $17.

I think I actually paid around $20 a bottle at the local Ford dealer. Online vendors seemed to average around $25-26.

Regardless, it's good stuff. I've heard a lot of scattered opinions about Amsoil this and Redline that... I've run the Redline MT90 in the past, and wasn't really impressed. I'm sure the stuff probably exhibits excellent longevity on the track, but it didn't seem any different from the cheapest GL4 I found at the FLAPS for daily-driver use in sub-freezing temps. I've found my new go-to oil.

Really interesting how you felt an immediate improvement. Whatever was in there must have been really old and terrible.
I've yet to experience any sort of "immediate, big" improvement on any transmission with any fluid. The differences are usually really subtle if at all noticeable.

Good to know. I plan on going this route as well. My MiataRoadster kit is still on my desk at home just waiting. :crx:

Hopefully the Amsoil is a improvement over redline when cold :vash: 1-2 shift drives me crazy in the morning.

While the gearbox was still nearly full, I would imagine that whatever was in there was the original 10 year old factory-fill with 130k miles on it. So, yes, this is obviously a case of replacing something that was ridiculously worn out with something that was not, but I wasn't expecting a simple oil change to make so huge a difference- I'd been assuming that I'd be shopping for a new transmission in the near future.



If nothing is broken, there's nothing to fix.

Unless you're in marketing.

I have the same problem as Joe every winter, almost feels like there's some kind of lock out on second gear. I usually just shift from 1st to 3rd until everything gets up to temp. Double clutching and rev matching don't phase it if its below like 40 degrees.

I put in Redline MTL last winter and didn't really see any improvement. I have been planning on rebuilding the shifter this winter since I know it needs new boots. Guess I'll give Motorcraft a try!

I've been running the Motorcraft for 5 years now. It's good stuff.

You all should qualify your statements with transmission type and usage. Remember Joe is talking about his DD 5 speed car here.

In my early-vin, narrow-shifter-ball 6speed, I have been running the Motorcraft for 5 years. In DD conditions. In Autocross. Through 30 track days.

Not the same 2 quarts for all of that obviously.

How thick is the Motorcraft stuff? Between 10w30 and gear oil, or straight up gear oil?

As I remember it, its pretty thin. Much closer to motor oil than gear oil. After mucking about with other gear oils I remember second guessing the Motorcraft stuff because it seemed much thinner. Joe can probably give you a better answer.

As I said in post 18, my 80K 5-speed XMSN was an immediate change from sluggish cold to smooth shifting when I put in the Motorcraft. Not needing a few week's of driving. I don't think Joe's experience was all that unique. It sounds like his unit was in much worse shape than mine, but I'm saying it does not have to be trash to see a change.

The other time I saw a drastic change was when Dad's 220D Mercedes manual had gear dope in it and we put in the correct ATF that was called for. THAT also had a drastic, immediate effect.

I plan to run the Dumondetech Fluid this year in Lazarus, super thick stuff, not great on the street, but should be pretty great for track use based on reviews I've seen from local peeps.

Where do you get your motorcraft. Local?