Cold Shift or Syncro Issue?

[wantin150]

Hey folks! I've got an issue with my 03 Toyota Matrix XRS, 2ZZGE 1.8l 6 speed manual (68200). I don't ever notice this in the summer of course, but here lately, when the temp is below 60F, I have a rough 2nd to 3rd shift. Almost feels like a grinding right before it goes into gear (fast upshift). If I shift slow, and ease the shifter into place, I can feel one little "bump" and it slides in. If I shift from 2nd to 4th and then to third (clutch in), there is no such feel. Once the fluid warms up, this goes away. If the temp is above 60F, there is no problem, even when the fluid is cold. I planned on changing the fluid at 75K but will do it at 70K to avoid further damage (if that's what's happening).

I guess my questions are these:

Cold shifting properties of the fluid? Too THIN at start-up? If this is the case, what can I mix to get the viscosity up some (currently running straight Redline MT90)? Maybe a 80W90 instead of 75W90?

Or are my third gear syncros going to pot?

Thanks in advance!

 

[Whimsey]

My experience is that the manual transmission fluid THINS out as it warms up. I have just the opposite problem. Mine shifts much better when cold and in cold temps. As it warms and in warmer/hot temps it can tend to crunch if I shift fast. The slower the shift, not too slow, it goes into gear better. Maybe your transmission fluid is too thick when it's cold. Is this the factory fill or did you replace it with something different already? How many miles on the fluid? If it's over 30,000 miles maybe it's just worn out. It certainly would not hurt to change it first to see it that makes a difference.

Whimsey

 

[JHZR2]

yep, at 4-5 years and nearly 70k, Id be thinking about swapping the fluid, first and foremost.

cold weather does all sorts of odd things to transmissions, especially all but the very best MTs.

That said, unless youre a really poor driver, and doo way too much downshifting into 3rd, Id find it hard to believe that your trans is bad.

Do the fluid changeand go from there... Its good PM all the same.

JMH

 

[mechtech2]

I'd change the fluid .
Amsoil has some very modern fluids that will work well.
But fluid is thicker when cold, and your transmission seems to like it when it's thinner.
Synthetic fluids are more stable at extreme temps.

 

[Jaykim81]

I would also change the gear oil. On every manual car I have owned the first thing I did was change the factory gear oil after a few thousand miles. I noticed that shifting always improved with new gear oil in the transmission. Also, after the gearbox is broken in, it's good to flush the particles from the oil that form while the moving parts wear in.

 

[Gary Allan]

I have to do it every few years with my wife's AX15. It uses Mopar GL-3 synthetic. All synth offerings are GL4 as far as I've found. 1-2 shift is still challenged in the cold if you don't take your time.

 

[unDummy]

Your fluid is too thick at startup.
And, you need to change the fluid more regularly.
Don't expect new fluid to make up for neglected maintenance intervals.

Amsoil, Redline, Ford, Motul, RoyalPurple, Synlube......make excellent gear oils. I would change out the gear oil now and make a habit of changing it every 30k miles!

You should UOA this 68k fluid.

 

[wantin150]

Just a little more info on the fluid. OEM fluid changed at 40k or so. Tried Amsoil SVG (GL5, trans IS rated for a GL4 or GL5) and hated it. Switched to Amsoil MTG, 75W90, GL4. Better than the SVG but wasn't 100% sold on it. Switched it to Redline MT90 at 50k so the current fill has almost 20k on it. I like how the Redline shifted when brand new.

Looking to maybe try the Redline MT90/MTL 50/50 mix if the fluid is too thick at start up.

 

[widman]

Without looking up the Redline specs, I'd bet it is too thick. Toyotas like the low end of the 75w-90, maybe lower. Many of the newer transmissions are going to 75W-80 or 75W-85 and reducing the additives to a GL3 to allow the synchronizers to grab better.

 

[aquariuscsm]

I`ve had a RL MTL/MT90 (3 quarts MTL and 1/2 quart MT90,I had some left over from awhile back so I topped it off with it) mix in my car for about a week now. Shifting action keeps getting better the more I drive it. Shifts with the OEM Nissan MTF had alot of metal to metal feel with some crunching/grinding shifts. With the RL MTL/MT90,the shifts feel very cushioned and the bearing rattle has almost completely disappeared.

I feel MTL is a very good manual transmission oil.

 

[double vanos]

Had the same problems with my Mazdaspeed 3. It specs 75w90 so I put in MT90....way too thick!

So, on advice I got here and with Redline's blessing, I did a 50/50 mix of MTL+MT90.

Shifting is much better when cold and really good when hot.

In the spring I am going to go straight MTL which is a 70/80 wt and that ought to wrap things up. If the car doesn,t like straight MTL, then I'll go back to the 50/50 mix. IMHO Mazda overspec'd their gear oil. Cheers!

 

[wantin150]

Looks like I'm headed toward the MTL/MT90 mix. I think I will try a 2 MTL and 1 MT90 (2.9 qts fill). Thanks for all the help. Keep 'em coming if you have more ideas.

 

[unDummy]

I would start with a 50:50 blend making it a solid 85wt(good for any 90wt requiring transmission).
Or, even run 1q MTL with 2qts MT90. Don't jump too thin.

 

[wantin150]

Thanks for the advice on the mix. I'll run 50/50 and see what that does. I can always drain a little and alter the mix later if need be.