Your choice for modern manual transmission fluid?

[Jeepridge]

Hi guys!

I know this is the sort of post that could cause family feuds, flame wars, and emotional meltdowns. SO… let’s please keep in mind that I am not asking for the “best”. I’m trying to get good advice from new friends about what they trust their six speed gearbox with. Let’s just be civilized here, okay? Preferably, something I can buy at NAPA, or O’Reilly’s since I have those fairly close at hand. If the answer is the factory MOPAR stuff, pass that along as well please. I can go by the closest dealership fairly soon.

Why am I asking? Well, there is nothing “wrong” with the transmission as is, but remember I bought this on 8/4 (with 133,000 miles on it) and the car records I have say nothing about changing transmission fluid though they did oil changes on time and even diff and transfer case services from time to time. So, I figured it would be better to be safe than sorry.



Thanks again guys, have a wonderful rest of your weekend now…


Jason

 

[Mopar]

Redline MTL. Not cheap but you don’t need much. Amazon has it

 

[Yittzy]

honestly man i just run whatever redline or mobil 1 synth is on sale at autozone. my manual's been fine on it. some guys swear by amsoil but i think they're just spending extra money. as long as you're not running like walmart brand garbage you'll be good. what trans you running?

 

[Jeepridge]

Sorry for not specifying, I did not know there were options on manual transmissions. I have the stock NSG370. At least that is what the build sheet says, it has a six speed manual with the MOPAR shift knob on it. So, I’m guessing it is the one it was “born” with.

I will likely get the Redline MTL now that I have some input on it. I can order it via Amazon, I’m the guy that usually prefers to shop local, so I’ll see if NAPA has it and not expect them to carry it.

I know there is some special little cut off Allen key tool you can get or fabricate for the drain plug above the exhaust, so I’ll check in on that too. I watched a video with an aluminum foil trick to keep the exhaust clean, looked pretty smart.

Anybody else? I am happy to hear any and all advice on the fluid, process, etc. And thanks!


Jason

 

[Mopar]

My JKU has an automatic but my TJ has the NSG370. It shifted the best on Redline MTL.

In addition, you need a GL4 oil. Most gear oils are GL5 and GL5 oils should not be used in a NSG370. Redline MTL is a GL4 oil.

 

[Jeepridge]

My JKU has an automatic but my TJ has the NSG370. It shifted the best on Redline MTL.

In addition, you need a GL4 oil. Most gear oils are GL5 and GL5 oils should not be used in a NSG370. Redline MTL is a GL4 oil.

Thank you!

A relaxing and edifying Sunday to you, sir…


Jason

 

[pc1p]

Redline MTL is popular in those applications that require GL-4. As others have said, you don't need much and it's readily available... I used it in my NSG, as well as my AX-15 for a long time and it worked great.

 

[Jeepridge]

Redline MTL is popular in those applications that require GL-4. As others have said, you don't need much and it's readily available... I used it in my NSG, as well as my AX-15 for a long time and it worked great.

I appreciate that! It is on order, and I will let you all know when I get it done and all is back together with a test drive! Have a great day guys!

Jason

 

[FirstLight]

Hi Jason,

I used to be a chemist in the late 1970s and one of my jobs was testing motor oil. I've been using Amsoil lubricants since the early 1980s. In my 2010 JK Rubi's manual transmission I use Amsoil MTF 5W-30 manual synchromesh transmission fluid and in my transfer case I use Amsoil ATF signature-series fluid. The reason I use the signature-series ATF is because of its extra-wide temperature range because I drive in some super chilly sub-zero Michigan winters.

My engine has over 140K miles and I'm now using Amsoil HM520 5W-20 High-Mileage series oil. For my front axle I'm using Amsoil AGL 80W-90 severe gear lube and for my rear axle Amsoil 75W-140 severe gear lube.

I purchased my JK used almost three years ago and I used ATS Chemical's 505CRO to flush the lower engine and 505CRF to flush the upper engine when I did my first oil change. All of the fluids have now been replaced, including the power steering and engine coolant.

I recently upgraded all of my brakes. I installed Mopar's J8 heavy-duty military master cylinder and booster (which required that I mod the clutch by adding a separate fluid reservoir for it). And I installed a PowerStop KC2798-36 kit with rotors, calipers and pads and PowerStop B941 parking brake pads plus seperately-sourced hardware. I used Amsoil DOT 3/4 synthetic brake fluid for a complete flush of the brakes (including the anti-lock brake controller) and the hydraulic clutch. It was a fairly big job.

I'll be doing my next engine oil change this September and, when I do, I'll be installing an oil pressure sensor from Banks to an unused oil galley port on the driver side of the block. I plan to connect it to my Banks iDash meter so I'll finally have an actual engine oil pressure reading. I hate the fact that Jeep provided only an "idiot light" on my JK for the oil pressure.

Kind regards, FirstLight