5 Speed Gearbox oil change 75w-90?

[Joker2]

Hello,
The service manual recommends 75W-85, GL-4. I am thinking about Motorcraft Synthetic GL-4 in 75W-90. I will sample the one removed to see how they compare. Anyone chose a different route? If so why? Any sample results?
Cheers.

 

[extremez31]

How many miles do you have on it? whats the service interval?

 

[Joker2]

32000 miles. Interval is TBD. On my Miata after 6000 miles including track days and a bunch of autocross events the diff oil has lots of iron bits and the tranny is fine. On the Mazda2 the oil is shared and I have done some track days and autocross events.

 

[Wall Of Death]

I did mine last month (15k miles) and used BG synchro shift II its a 75w80 but the gearbox feels like new again. The biggest improvement is going into 1st/reverse when cold. Over the years I have used a quite a few gear oils and as far as transmissions go the best I have used have been bg and Amsoil both on the street and track. I had only used the original BG syncroshift before but I wanted to try the newer BG Synco Shift II since it is designed specifically for FWD Manual gear boxes. Love it so far 2000 miles later.

with that said, the motorcraft should be fine as well and that goes for most any quality gear oils as long as you stick with a GL-4 you will be A-OK.

Also the service interval for transmission fluid is usually 30k depending on use. I tend to stick with 15k though as I feel like after 10k miles or so of street driving things tend start feeling a bit clunkier than they did when they were new. Its a small price to pay for smooth shifts and a long gearbox life especially if you change the fluid yourself.

 

[Joker2]

Nice feedback, thank you.

 

[zps2004]

I have had good luck with Royal Purple in the past. I will probably use that in my 2 when I change it or Amsoil. Almost at 43K right now. I will probably change the oil at 50K. My car used to see a lot of highway before we bought a house thus the higher mileage.

 

[CorkSport]

I went with redline in our shop car. My other choice has been torco in the past which worked well in my 323gtx.

Derrick

 

[zps2004]

mmmm 323GTX

 

[Wall Of Death]

Derrick is right, Redline makes some good stuff too. I actually have MT-90/MTL in one of my cars now with no complaints either. FYI if you do go redline mix 2 MT-90's + 1 MTL you will end up with a 75w-85

 

[Tom_Mazda2]

I did mine last month (15k miles) and used BG synchro shift II its a 75w80 but the gearbox feels like new again. The biggest improvement is going into 1st/reverse when cold. Over the years I have used a quite a few gear oils and as far as transmissions go the best I have used have been bg and Amsoil both on the street and track. I had only used the original BG syncroshift before but I wanted to try the newer BG Synco Shift II since it is designed specifically for FWD Manual gear boxes. Love it so far 2000 miles later.

with that said, the motorcraft should be fine as well and that goes for most any quality gear oils as long as you stick with a GL-4 you will be A-OK.

Also the service interval for transmission fluid is usually 30k depending on use. I tend to stick with 15k though as I feel like after 10k miles or so of street driving things tend start feeling a bit clunkier than they did when they were new. Its a small price to pay for smooth shifts and a long gearbox life especially if you change the fluid yourself.

Thanks! That's some really good advice. Looks like I'm going to have to go with some BG Synchro Shift II for my Mazda2.

My Mazda2 is approaching 15,000 miles but I also have done about 10 track days and a few autocross events. I believe it is time to replace the gear oil in my transmission.

 

[CorkSport]

Thanks! That's some really good advice. Looks like I'm going to have to go with some BG Synchro Shift II for my Mazda2.

My Mazda2 is approaching 15,000 miles but I also have done about 10 track days and a few autocross events. I believe it is time to replace the gear oil in my transmission.

Our B-Spec fluid looked pretty ugly with only 10k on it when we changed it out. Full throttle everywhere does put a load on things.

-Derrick

 

[Tom_Mazda2]

Our B-Spec fluid looked pretty ugly with only 10k on it when we changed it out. Full throttle everywhere does put a load on things.

-Derrick

I can only imagine how bad the oil from my tranny is going to look. While I renew the oil in my transmission I'm also going to do a radiator flush and put in some 50/50 coolant.

 

[ngd298]

I'm going to change mine in the next few weeks (50k) I'm debating between Pennzoil Syncromesh and some kind of synthetic, like Amsoil or Redline. What do you guys think? A lot of people swear by the syncromesh, but I use synthetic oil, so I feel like synthetic gear oil would make more sense.

 

[Joker2]

Give me a few weeks and I'll let you know if the Motorcraft stuff works. You can always do the Honda MTL from your local dealer. GL-4.

 

[AN7]

I am going with Amsoil MTG.

I have also used RedLine MT90 but i didn't like that much in the cold mornings.

 

[Joker2]

A few hundred miles and it's all good. The Motorcraft stuff works. Shifts like butah! 76 bucks later. Our tranny takes 3.1 quarts so 4 quarts of GL4 at 18/quart. Be back in a few more weeks with an oil analysis of the old stuff.

 

[utmorpheus]

A few hundred miles and it's all good. The Motorcraft stuff works. Shifts like butah! 76 bucks later. Our tranny takes 3.1 quarts so 4 quarts of GL4 at 18/quart. Be back in a few more weeks with an oil analysis of the old stuff.

Glad to hear, since I just picked up 3 Qt of it. With only 2500 miles on the factory fill it's already getting dodgy when warm; cold it shifts fine. Going to change out to Mobil1 engine oil and the FoMoCo pixie oil at 3k.

 

[02semiata]

Changing mine to redline MTL just like I ran in the miata. Can anyone post or point me to a "how to" for the gearbox oil change. Thank you

 

[02semiata]

Bump any one ???

 

[CorkSport]

I don't have a how to but it is pretty easy. I believe the drain and the fill are 23mm sized. The drain is right on the bottom and the fill is 1/2 up the case on the front of the gearbox. When I did it I used a funnel and a section of vinyl hose so I could see how where the fluid is.

Thanks
Derrick