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First gear slight grind once in a while?

Hey there sometimes when going into first gear from a complete stop will grind slightly what could be the cause of this? It seems to only do it after driving a little while. Also I checked to see if the push rod maybe needed to be loosened but it cant be loosened any further. The rest of the gears don’t seem to have any issues at all and it doesn’t have a problem accelerating at all could I possibly just be doing something wrong? The previous owner said they had no problems with the clutch whatsoever and they have driven manuals for 50 years. Someone that I know told me that they have that happen with all the manuals they have driven but I don’t know just want to make sure I know whats up.

Also I noticed that the master cylinder wasn’t fully bolted into the firewall and caused it to squeak when I pushed in the clutch I just fixed this don’t think it would cause an issue though? One last thing when I adjusted the rod after installing it because I had it all the way tightened before and it wouldn’t go into any gear I didn’t bleed it again as I had already bleed it with it all the way tight but was wondering now that is loosened all the way would I have to bleed again?

Either the clutch is dragging for whatever reason; meaning it’s not disengaging completely with the pedal depressed or there is wear in the synchronizer hub unit and often caused by forcing it into gear.

This is more noticeable on 1st and 2nd gear as the gears are more straight cut; not beveled as much as 3/4/5.

Try only shifting to first gear from second gear. I developed this habit driving British sports cars with no first gear synchronizer which would occasionally grind a bit when shifted to first gear at a full stop from third, fourth or neutral. I never experienced any grinding with my 2002 Eclipse but I always used the second to first procedure.

If the clutch master cylinder isn’t securely bolted to the firewall, that could cause all sorts of shifting problems including this. As can a pushrod incorrectly adjusted to the wrong length. Get those problems fixed and tested before moving on to other possibilities.

Fixed the cylinder not being bolted down all the way. I checked the push rod related to the service manual and the free play and height. The free play is off of the minimum by 1mm. Also I drove it a bit just now and it seems to me that shifting from 2nd to first is smoother at a stop but I only drove it a few minutes so I’ll have to wait till I drive it a bit more for that assumption.

Also if the transmission fluid is old could it cause this problem? The car sat for around a whole year or so and I haven’t changed it and not sure when it was done last.

Is that at the pedal or the pushrod? If at the pedal, that’s nothing to be concerned about. Spot on is preferred, but It’s better to have a little bit too much free play than too little.

Unlikely to be the cause. It’s always a good idea to check the transmission fluid level though, make sure it is topped off. Just for the health of the transmission. You or your shop can get a judge of the fluid’s condition then too. Be aware that engaging first gear is generally the hardest of all the gears to engage, other than perhaps reverse, so some difficulty and perhaps a little grinding noise is to be expected. If the grinding sound is reduced significantly by pumping the clutch pedal two or three times in rapid succession prior to shifting into first, that could mean the clutch master cylinder seals are leaking and it needs to be replaced.

Yes the freeplay was at the pedal. How do you get more or less freeplay? Just by bleeding or is there an adjustment for that too? I recently replaced the master cylinder and slave not sure if I got the rubber boot on the slave rod on all the way though as I kinda was having a hard time with it.

So then it is normal for it to do a slight grind every so often in first gear it’s barely noticeable. Thats good to hear as I was worried that I may have 2k worth of work soon or something. I haven’t experienced any grinding in reverse yet but probably because I don’t drive it a whole lot.

I’ll check the transmission fluid after I get a new ignition coil and spark plugs. I only drive the car once a week currently so it shouldn’t be to much of a problem. Also I’ll try the pedal pump just to make sure as well. Thank you for everything. :slightly_smiling_face:

You should have 1 inch of freeplay at the pedal the adjustmemt should be at the slave cylinder.

I think my slave is self adjusting I didn’t see anyway to adjust it and that’s what I read over at club3g. I’ve been adjusting the pedal where the master cylinder rod goes in but it really doesn’t seem to do much other then if it’s to tight it won’t shift at all.

The suggested one inch of free play is to prevent it from being too tight.

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1/8" is plenty of free-play for a hydraulic clutch. You are only dealing with the distance between the clutch pedal and the master cylinder, there will never be enough heat in the cabin to cause the push rod to expand an inch.

I used to have a Subaru Outback with manual transmission and it would grind the 1st gear when shifted not carefully.
Since it was time to replace fluid anyway, I’ve changed with “some” gear oil of proper specification, and it became MUCH WORSE :frowning:
At that point I’ve started reading Subaru forums on this topic and found you have to stick either to Subaru branded gear oil or go with specific ones, known to be good to this particular car.
Upon replacing gear oil to recommended Valvoline, it made shifts very smooth, much better than before I replaced original fluid.

I would recommend checking Mitsu forums for recommendations from people who did it before.

First, follow all the suggestions of those here to make sure the cylinder issues are corrected as that could definitely be the issue. Solving this will eliminate one variable.

Second, you can move on to the fluid and such. By “old”, do you mean the original fluid or just old fluid? I have changed manual transmissions where the fluid is just filthy, broken down, and full of wear metals. It is apparent many people think that they never need to change the manual transmission fluid. When I come across these I refill with the cheapest motor oil in the 5W30-10W30 range and drive it 10-20 miles to “flush” the transmission. I then drain and refill with the “correct” fluid.

Use of traditional gear oil may do more harm than good, especially to the synchronizers which is one possibility for your issues. Make sure you use a fluid that is designed for “yellow metal compatibility” as traditional gear oil will damage most synchronizers. Some manual transmissions even call for standard automatic transmission fluid.

I also agree that checking the forums for what works best on this car is the way to go. Remember that this car is now 15 years old and lubricant technology has changed a lot in that time. These cars do have a following so am sure someone will have an opinion.

eclipse mitsubishi

(Please see illustration below…)
:red_car::man_mechanic:t2: :woman_mechanic:t2: :man_mechanic:t2: :woman_mechanic:t2: :man_mechanic:t2: :woman_mechanic:t2:

Sorry, I couldn’t stop myself!
CSA :laughing:

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I’ll be working on fixing the cylinder tomorrow. Also as for the transmission fluid I dont know if it’s the original or not it very well could be the tires on the car were 8 years old so I can tell it wasn’t maintained much. The previous owner told me he didn’t know any work that had been done previous and he only changed the battery and kept the oil and wiper fluid topped off. He only put about 8,000 miles on it and had it about a year.

Also would flushing and putting what the manual calls for not be a good idea do to the wear that it may have? I heard that somewhere not sure if that’s true or not. I’ll have to look further into what others maybe recommend over on club3g for it’s age and mileage.

So he never changed the oil or filter. I’d do that first thing. And have the car completely checked over.

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Confusing part with my Subie example was that I’ve carefully matched the specified weight/grade/etc…, and still got worse result, so even within the spec, it is enough variation for the synchronizers to behave not as intended

I replaced the oil pan a few months back as well as replaced the filter. Also about how much would a 100% inspection cost? I’ll probably have to wait till I start working again after this semester.

Your vehicle was recently inspected when you had all those repairs done (suspension, brakes, lights,exhaust etc.).

Back in my early driving days with three speed transmissions, unsynchronized low gear and the column shifter, before I would shift into low gear at a stop, with the clutch depressed, I would move the lever to second gear and then into first. That eliminated any gear grind. I don’t see why the same method wouldn’t work on the OP’s car. The synchronizer for first gear may be slightly worn.