Grinding when going into fifth gear MT

[Ausfahrt]

My 2014 Subaru Crosstrek has been occasionally experiencing a momentary grinding of gears when shifting into 5th (top) gear. It doesn't happen all the time but it does seem to slowly be getting worse. Pausing in neutral before upshifting into 5th seems to help. The car has 158000 miles on it and I had the clutch replaced at 130000 because the throwout bearing was bad. I think that my wife's penchant for keeping the clutch pedal depressed at stop lights in rush hour traffic was the culprit. (Gotta blame the wife LOL)

Anyway, the car is now ten years old and we bought it new. I'd love to get another 2-3 years out of it and get to 200k and I think that we can since it is now just our winter beater car.

I don't know how synchronizers in manual transmissions work but I suspect that may be the issue.

 

[3783-KC1]

Dunno how they work too much either, but that sounds like it is it. Sounds like you are matching the revs better when you wait. Maybe see if there is a Redline MTF that suits your specs? From the little I have heard, Redline's MTFs work great in a lot of transmissions and may help a little.

Have no idea though...

 

[harbor]

Agree on trying new tranny fluid. I’m sure the Suby owners forum has a favorite fluid like RedLine, Amsoil, HPL, Schaffers, etc.

 

[KrisZ]

Double clutch the fifth gear and you will be fine.
Also, check gear oil level, it might be low

 

[nwjones18]

I have the same symptoms with 3rd gear on my Mazda. I try not to slam it into 3rd any more than I need to. I have Redline MT90 in there now (if I remember correctly, know its Redline something) so I have a hard time believing different fluid would change anything.

 

[FowVay]

A change from the factory 75W-85 MTL in my Nissan Frontier to Amsoil 75W-90 MTL eliminated the 5th gear crunch. However, my truck's transmission is terrible with the 1-2 shift and the fluid change did nothing for that problem.

 

[Chris142]

Double clutch going into that gear.

 

[LazyDog]

Just something else to keep in mind, my friend had a 2011 Forester w/ 68K and one day it would not shift to some gears.

After an inspection, they found out that the fork had broken inside the trans. After some back and forth Email w/ Subaru they agree that my friend will pay for the parts and Subaru the labor. This was back in 2019.

 

[KrisZ]

Another thing I just remembered, check the shifter mechanism and linkage at both ends for play. Could be something as simple as a worrn out bushing.

 

[Overfill]

@MolaKule, I'm a little braindead today, but would synchronizer FM alleviate this, or is this operator error?

 

[chris719]

Operator error? I think this is just a Subaru doing Subaru things. Operator error doesn't usually destroy the 5th gear synchro.

 

[Rand]

Try changing the fluid its picky and needs a GL-5 gear oil that is ok for manual transmission with synchros.

 

[JohnnyJohnson]

Have you ever check the gear oil level or change the gear oil? Should have probably been done a couple times in 130,000 miles.

 

[ecotourist]

When driving a manual transmission I try to "wish it" into the next gear. By that I mean shifting so smoothly and gently the transmission just drops into gear. Though it might sound a bit like "Zen and Art of Motorcycle Maintenance", shifting that way gives you a feeling of one-ness with your vehicle. I find that holding the shifter with only three fingers (rather than a fist) really helps.

And of course double clutching will solve most grinding problems.

I like the suggestion of checking for excess play as well. Could be something as simple as that.

 

[bullwinkle]

When driving a manual transmission I try to "wish it" into the next gear. By that I mean shifting so smoothly and gently the transmission just drops into gear. Though it might sound a bit like "Zen and Art of Motorcycle Maintenance", shifting that way gives you a feeling of one-ness with your vehicle. I find that holding the shifter with only three fingers (rather than a fist) really helps.

And of course double clutching will solve most grinding problems.

I like the suggestion of checking for excess play as well. Could be something as simple as that.

Rev matching does seem to help-run it up a little more in 4th, push in the clutch, let the RPMs drop to where they normally would be for the speed.

 

[SubLGT]

Drain the old gear oil, replace with Motul Gear300 75W-90 GL5.

 

[demarpaint]

I'd bleed the clutch to swap out the old fluid, along with changing the transmission fluid. Bleeding the clutch often helps with grinding problems.

 

[Ausfahrt]

Thanks for the replies. I do have redline MT fluid in there and I will check the level.

Double clutching does alleviate the problem but I don't always remember to do that especially since it doesn't grind every time.

 

[ammolab]

5th gear is very small and has little rotational inertia. It is the easiest gear in the tranny for a synchro to mate up the gear set. If you can sync it by double clutching? I suspect a very lazy synchro.

 

[SHOZ]

My Gen Coupe will grind on 3d and 5th if you are too quick. I found a lighter fluid and Ceratec help quite a bit.