Manual Transmission Fluid GL-4 75W-80

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CX-5 Sport 6MT
I'm past due for service and my dealership doesn't cover this as part of their maintenance program. What is used for factory fill? The owner's manual only says they recommend GL-4 in 75W-80 viscosity with a blanket Castrol endorsement. I haven't been able to find Castrol GL-4 75W-80 (in the US) so I'm looking for alternatives.

I'm looking at Redline or Pentosin, but that's really the only to options I've been able to find that meet the GL-4 75W-80 requirements. Does anyone have any other recommendations or experience with these? I do get a bit of grind if I run 1st up to redline and try to shift to 2nd too quickly so I'm looking to fix that problem with the change.
 
I'm looking at Redline or Pentosin, but that's really the only to options I've been able to find that meet the GL-4 75W-80 requirements. Does anyone have any other recommendations or experience with these? I do get a bit of grind if I run 1st up to redline and try to shift to 2nd too quickly so I'm looking to fix that problem with the change.

I assume 2nd gear has synchromesh (designed to spin the gear up to a matching speed right before it engages). The only way to fix the problem you speak of with oil is to use a less slippery and/or thinner oil. And I wouldn't recommend messing with either of those things due to concerns about longevity and also worse fuel economy. The proper fix is to change the way you apply shift action. There should be a point of extra resistance right before the engagement (grinding) is happening. That is where the syncros are spinning against each other to spin the gear up to proper speed right before it engages. Gears have mass so this takes a perceptible amount of time. Rather than trying to slam by this point of resistance in one fast stroke, apply pressure to that point of resistance for a split second and then increase the pressure, but only slightly, to engage the gears. It's all about applying pressure to the syncros for a brief moment before engagement. Most units will fall into gear on their own at the appropriate time if you get the pressure right.
 
Hmm, I think JBR and corksport offer short shifter kits which may suit your driving style better.
 
I appreciate the recommendations for changing my shifting style and installing a short shift kit, but neither of these help me locate a correct MTF for my car that needs a tranny fluid change.

Can anyone recommend a GL-4 approved Manual Transmission Fluid in 75W-80 grade?

Since the vast majority of the drivers here have autos, I may need to look elsewhere for an answers. I will post back here after I find the information I'm looking for.
 
Can anyone recommend a GL-4 approved Manual Transmission Fluid in 75W-80 grade?

How many miles are you at? I'm at 45k, but I don't really feel the urge to swap out my transmission fluid yet.

Try some mazda 3 forums for more info. They use the same exact transmission as we do (even same exact gear ratios on some models)
 
I decided to pick up two quarts at my local Mazda dealership. They cost $28.66 for a quart! They mentioned that their retail price for this is $42.99 and they were giving me a "discount." I do get free lifetime oil changes with the Mazda moly oil at the same location, which does lessen the sting a bit. This stuff is obviously available online for less, but when you factor in shipping it ended up being about the same. The bottle information is minimal. It only says "premium long life gear oil SAE 75W-80." No mention of any synchro additives or enhancers. I would normally associate long life manual transmission fluid with longer change intervals than 30k miles. I'm wondering if this is a newer product that was introduced for the SkyActiv models (like the moly motor oil). I'm at 31K miles and my scheduled maintenance book says the manual transmission fluid should be changed every 30k. My car was built in 04/2012 so maybe my documentation is wrong or they didn't have the long life formula when my car was built. Some Mazda 3 owners indicated that adjusting the linkage can help with 1-2 grind if changing the fluid doesn't help. I had narrowed down the alternatives to Redline MTL 75W80, Pentonsin MTF2 or Fuchs Titan Sintofluid FE SAE 75W. The Mazda brand fluid is probably designed for fuel economy. I'm not sure it's the best for enhancing synchro friction. The Pentosin and Fuchs are also quite pricey and run about $25/liter. Redline is around $15 per quart. I'll report back the results after I swap in the new stuff. If there is no change the next step may be CorkSport short shift kit.

For reference the part number is: 0000-77-5W80-QT

Here's some photos of the bottle front and back:
19485141840_44cd08bb88_b.jpg

19050542354_41d9483fc9_b.jpg
 
Edited, it's not the same oil used for the diff/transfer case.
 
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Hi All,

FWIW, I just changed the transmission fluid on my Sport manual 2013 with the Redline MTL (75W-80) at 50k miles. I was surprised how dark the factory fill was after just 50k - looked like the stuff I used to drain from my lawnmower! Regardless, I am happy with the new shift feel and my ScanGauge reports 2+MPG improvement in my regular commute! I know, not very scientific since it's only been 3 days since I changed the fluid...(spin)
 
Hi All,

FWIW, I just changed the transmission fluid on my Sport manual 2013 with the Redline MTL (75W-80) at 50k miles. I was surprised how dark the factory fill was after just 50k - looked like the stuff I used to drain from my lawnmower! Regardless, I am happy with the new shift feel and my ScanGauge reports 2+MPG improvement in my regular commute! I know, not very scientific since it's only been 3 days since I changed the fluid...(spin)
change interval on a Miata is 30k and the fluid is pretty dark by then. So it doesn't surprise me that it's pretty grim by 50k. Redline is good stuff. Made quite a difference in shift feel on my two MX-5s.
 
I need to do the fluid in mine. I haven't diy this beforel Any hints to the process? I've done water pumps, exhaust/intake gaskets, turbo replacements and feel reasonably compentent.

Hi All,

FWIW, I just changed the transmission fluid on my Sport manual 2013 with the Redline MTL (75W-80) at 50k miles. I was surprised how dark the factory fill was after just 50k - looked like the stuff I used to drain from my lawnmower! Regardless, I am happy with the new shift feel and my ScanGauge reports 2+MPG improvement in my regular commute! I know, not very scientific since it's only been 3 days since I changed the fluid...(spin)
 
It's not that difficult - easier than an engine oil change IMO. The hardest part was removing the entire skid plate - it seemed like 20+ fasteners! Really wish Mazda hadn't used so many plastic 'snap' connectors for the skid plate - makes the whole assembly seem flimsy...(uhm)

Recommend you get a copy of the on-line service manual (plenty of links in this forum) that shows the transmission service instructions and fill/drain plug locations.

Good luck!
 
It's not that difficult - easier than an engine oil change IMO. The hardest part was removing the entire skid plate - it seemed like 20+ fasteners! Really wish Mazda hadn't used so many plastic 'snap' connectors for the skid plate - makes the whole assembly seem flimsy...

The CX-5 doesn't come with a skid plate (and doesn't need one IMO).
 
Apologies for not being precise. I was referring to the 'Front Under Cover No.2' as identified in the 2013-CX-5 Body and Accessories Workshop manual.
 
No worries Martin. Most of us have looked at the under side of the car and know what you're really talking about.
 
No worries Martin. Most of us have looked at the under side of the car and know what you're really talking about.

Absolutely! I knew what Martin was talking about but just wanted to clarify for those who are still looking for their next vehicle and who might not know as much about the CX-5 as us owners who have poked around it a bit.
 
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