Manual transmission flush?

Rustynj

Rustynj

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Ever since I changed out my trans fluid I’ve been getting a chirping sound. I’m starting to think my pump had other fluid in it (diff) and contaminated the trans.

I’d like to do the equivalent of a transmission flush. Anyone do such a thing?

Maybe remove the shifter and send a shit ton of brake clean thru it?
 
Rustynj said:
I’m starting to think my pump had other fluid in it (diff)
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Pump? Your info say you have a manual trans, so no pump.

What oil did you put in? Describe the noise better, like when does it happen? Is it constant, only when shifting etc.?
 
Rustynj said:
Ever since I changed out my trans fluid I’ve been getting a chirping sound. I’m starting to think my pump had other fluid in it (diff) and contaminated the trans.

I’d like to do the equivalent of a transmission flush. Anyone do such a thing?

Maybe remove the shifter and send a shit ton of brake clean thru it?
Click to expand...
You have a manual transmission so there's no need for a flush, just a simple drain and fill is good enough. I'd go strictly with Redline MTL for the new gear lube, what did you use before? Redline MTL is rarely found in auto parts stores, I'd get it on Amazon.
 
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Jerry Bransford said:
You have a manual transmission so there's no need for a flush, just a simple drain and fill is good enough. I'd go strictly with Redline MTL for the new gear lube, what did you use before? Redline MTL is rarely found in auto parts stores, I'd get it on Amazon.
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I used MTL but I think there was a little diff fluid in the hose when i put it in. I have no other explanation for the new sound from the trans.

And to the other guy how are you going to get the fluid in without the hand pump? Just squirting it in?
 
Rustynj said:
And to the other guy how are you going to get the fluid in without the hand pump? Just squirting it in?
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You never mentioned a hand transfer pump so that's what I was confused about, thinking maybe you assumed a manual trans had a pump like an automatic, and yes, you can just squirt it in which is how I always wind up doing it.

To address your concerns of contamination, no, a little gear oil isn't going to hurt anything.

Again I'll ask, is it a constant sound or only when shifting?
 
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Any residual gear oil in the pump hose won't affect your manual trans. There was probably less than a quarter of an ounce in there.

Ill be one to say I dislike MTL. Very notchy feeling in my AX15.

Is it a rotational chirp? Likely you have a ujoint or double cardan joint starting to fail.
 
Rustynj said:
I used MTL but I think there was a little diff fluid in the hose when i put it in. I have no other explanation for the new sound from the trans.

And to the other guy how are you going to get the fluid in without the hand pump? Just squirting it in?
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That little bit of differential lube in the hose wouldn't have caused a problem. It is still a gear lube and some differential lubes are 100% fine in the transmission.
 
It is a slight whistle / chirp coming from the front of the transmission. It’s driving me crazy. Happens when idling and when driving.
 
Jerry Bransford said:
There goes my bad throwout bearing theory lol.
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That's what I was expecting to say too.

Rustynj said:
It is a slight whistle / chirp coming from the front of the transmission. It’s driving me crazy. Happens when idling and when driving.
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Does it change in pitch and/or volume with RPM? Does it do this while sitting still or while moving?
 
BlueC said:
That's what I was expecting to say too.



Does it change in pitch and/or volume with RPM? Does it do this while sitting still or while moving?
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Consistent. Volume may go up when driving.

Sitting and moving. Sometimes it takes a break or I forget about it b
 
Rustynj said:
Consistent. Volume may go up when driving.

Sitting and moving. Sometimes it takes a break or I forget about it b
Click to expand...

Sounds like it's on your input shaft. Since you say it doesn't go away with the clutch pedal, and assuming you used a proper MTF, then it's likely a bearing inside the trans. It's best to find a second reputable local shop and let them diagnose it, even if that cost you $20.
 
BlueC said:
Sounds like it's on your input shaft. Since you say it doesn't go away with the clutch pedal, and assuming you used a proper MTF, then it's likely a bearing inside the trans. It's best to find a second reputable local shop and let them diagnose it, even if that cost you $20.
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Meaning I could be looking at a trans rebuild if the sound gets too annoying. Right now its bearable. Not a loud sound. Just bothering me.
 
tworley said:
Ill be one to say I dislike MTL. Very notchy feeling in my AX15.
Click to expand...
Since I have only 200 miles on my new AX15 (replaced the original NP3550), I noticed your dislike of Red Line MTL. That oil was brilliant in my 3550, but the forum consensus is to use Red Line MT-90 in the AX15. I bought a case on Amazon.

I don't know what notchy means, but my AX15 has a B&M short throw shifter on it and the first 200 miles have smoothed the shifts noticeably. Needs a vigorous push to engage now, but I will give it more time. The 3550 reverse was synchromesh, the AX15 reverse is not, so I have to return to the technique I used on my Scout T19, select 1st before reverse.

Already, I like it better the more I drive it.
 
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Mark K said:
Since I have only 200 miles on my new AX15 (replaced the original NP3550), I noticed your dislike of Red Line MTL. That oil was brilliant in my 3550, but the forum consensus is to use Red Line MT-90 in the AX15. I bought a case on Amazon.

I don't know what notchy means, but my AX15 has a B&M short throw shifter on it and the first 200 miles have smoothed the shifts noticeably. Needs a vigorous push to engage now, but I will give it more time. The 3550 reverse was synchromesh, the AX15 reverse is not, so I have to return to the technique I used on my Scout T19, select 1st before reverse.

Already, I like it better the more I drive it.
Click to expand...

B&M def starts out difficult but I can see mines breaking in decently.

So no votes for changing out the tranny fluid again huh?
 
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Mark K said:
Since I have only 200 miles on my new AX15 (replaced the original NP3550), I noticed your dislike of Red Line MTL. That oil was brilliant in my 3550, but the forum consensus is to use Red Line MT-90 in the AX15. I bought a case on Amazon.

I don't know what notchy means, but my AX15 has a B&M short throw shifter on it and the first 200 miles have smoothed the shifts noticeably. Needs a vigorous push to engage now, but I will give it more time. The 3550 reverse was synchromesh, the AX15 reverse is not, so I have to return to the technique I used on my Scout T19, select 1st before reverse.

Already, I like it better the more I drive it.
Click to expand...

Correction--I dislike Red Line MT-90. Very notchy feeling in my AX15:)

I had pennzoil synchromesh in there before and it was very smooth and glided into the gear position. Redline is different in that I can feel the point in which I have to overcome the engagement to get it to be where I need it. Its not a daily driver so perhaps Ill kick that can of changing it down the road until next season.
 
tworley said:
Correction--I dislike Red Line MT-90. Very notchy feeling in my AX15:)
Click to expand...
The official Aisin recommendation for the AX15 is GL-4 75W-90 which is exactly what Redline's MT-90 is. It felt fine in my AX15, I liked it... and no notchiness whatsover.
 
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