Where I live during the winter we have temperatures where it is -30C to-40C for weeks at a time. Sometimes the clutch freezes up and I have to use the clutch start/cancel button to even get the truck started. Even when I let it warm up the clutch is hard to operate. Can anybody recommend me a better transmission fluid I could use for winter that would be safe for the vehicle?

I wish I was in Cancun with this weather!

Can you explain what you mean better please? Can you push the clutch in or is the foot pedal stuck? Maybe the cold is freezing some stuff up and just need to break loose? idk

Im mostly just curious but once the car is started does it just fix it or slowly get easier to press as the vehicle warms?


The clutch isn't in any oil so I wouldn't imagine oil would have much of a difference for the clutch. I don't think a manual transmission oil be effected too much since its not really pumping the oil around only spinning inside of it..

In cold weather the transmission fluid viscosity should only affect shifting.

If it's your clutch pedal giving you problems, how long it been since you changed fluid.
Same as brake fluid, has a tendency to absorb moisture and freeze it.

Just replaced the transmission oil in the summer. Everything works perfectly when it's warmer. Clutch is new as well as a rebuilt tranny. Haven't put a lot of miles on it since then either. Here's a better description of my issue: I step on the clutch to turn the engine on. It is difficult to push it in all the way. It doesn't stick but is very slow/heavy. You know how you have to push the clutch all the way down to start it? In the severe cold, even with the clutch pushed in as best as it can, the car doesnt seem to recognize that its pushed in and won't let me turn it on. Shifting is brutal unless its been warmed up for half an hour or if I have been driving for a long time.

I second 96Red's thought that this is probably hydraulics related.

What transmission fluid did you use? Use Amsoil or Redline MT90. You want GL4. Anything GL5 may contain sulphur which eats syncrhos and causes bad shifting.

Possibly the sensors in the pedal area aren't properly sensing that the pedal is depressed.

I would try flushing the hydraulic clutch system. Its most likely brake fluid in there which can absorb moisture and freeze, which sounds like what you're experiencing....

It'll get better come spring time !!

This sounds like the solution. Sounds like I should change my clutch and brake fluid!

I dont have any heaviness or extra pressure on the clutch but my switch is a little iffy sometimes and wont react until i really mash the pedal. Several times i thought my battery was taking a dump but the switch just wasn't activating

new clutch, master, slave and fluid on mine but I haven't adjusted the switch yet, will report back if i do.

I know what you mean about the clutch switch. You really have to get the clutch right down into the carpet to activate the switch, which is hard to do at -40.

I found my switch is NOT adjustable. I put a little 1/8 " thick self stick rubber bumper (like for a cupboard door) on the pedals contact point. This raises the switch point out of the carpet. Pulling the clutch pedal out and cleaning/greasing its pivot shaft helps with clutch pressure required. They dry out.

As for gear oil, Amsoil or Redline GL-4 as mentioned. Mine really likes the Amsoil best, others prefer the Redline.

I don't drive my 4runner in the winter if I can help it, so this is a Corolla solution. Stick a little 75W heat pad on the tranny bottom so that when you plug in the block heater you are also warming the transmission. This makes a HUGE difference in cold weather startup. It'll shift like a warm transmission.

Good luck!

Thank you for your detailed answer! This is exactly what I think I need!

For shifting purposes you could also source a 70W-80 or 75W-85 rather than the typical 75W-90 like Amsoil MTG or Redline MT-90.

You can run these lower weight gear oils in cold weather without issue as long as they still have a GL-4 wear package.

i'll be doing that now thanks