Manual shifting trouble.

[N8inVT]

Have a manual 87 that has been getting harder to put in any gear, i know i have a bad tranny mount. When i back up it gives that bucking feel, not horrible, but its an issue on the list....my question, could that be part of the reason for the hard shifting? It doesnt always do it, but becoming more frequent. Ive also noticed that it seems like i need more clutch, like when i go down a hill with clutch fully pressed, i can still feel the tranny slowing the vehicle down as if the clutch is being let out. Bad clutch.... or would a bad tranny mount be triggering these issues? 

[cruiser54]

Likely unrelated.

How's the fluid level in the clutch master? condition of the fluid? 

Last time you checked and topped off trans fluid?

[N8inVT]

Clutch fluid is full but color is kind of dark. Havent got down to check tranny fluid yet, but now its on the list.

[cruiser54]

Keep us informed. 

It wouldn't hurt to suck the old fluid out of the clutch master.

Then, best you can, get the crap/sediment out of it. Add new fluid and pump the hell out of it. You may be tempted to do that a second time. 

[Tactical Bacon]

Had a very similar problem in my 91 MJ 4.0 AX15. I could bleed the clutch hydraulics and the problem would disappear for a few weeks then return. It ended up being a faulty slave cylinder in my case but a faulty pressure plate can cause similar symptoms.

 

Definitely recommend replacing the fluid in the clutch system with new and if it has a bleeder screw, try to bleed it, too.

[N8inVT]

Ok, so i sucked the old fluid out of the master cylinder, it was definitely in need of changing, black color. After bleeding it several times and refilling slave with fresh fluid the color started getting slightly better, but still needs more work. Major difference in shifting noticed right away. Shifting much better, have not had any problems getting it into gear, but its not perfect yet, much better, so I'm assuming when i finish flushing it and get the black color out it should be back to normal. I was thinking throw out bearing, glad you guys pointed out the simple place to start. Saved me time and money. Will update when i finish the flush out.

[cruiser54]

After that, or even now for that matter, pump the pedal about 50 times and walk away for 20 minutes. See how that works for ya. 

[N8inVT]

So it worked well for a day, started acting up again, beginning to think i may need a new slave cylinder? I know i have more flushing to do, still has a blackish color. Will try pumping it up more as mentioned in the mean time.

[cruiser54]

Good plan for now. 

If a slave cylinder is bad, there should be fluid leaking between engine and trans.

[N8inVT]

 Update*

So today before leaving, i pumped brakes 40 times or so, shifting was better, but got harder after a few miles( in town, lights and stop signs) i noticed that if i pumped the clutch while sitting at red light shifting became easier. Got home, checked a

[N8inVT]

Checked above fuse panel under clutch, found a small drip. Have i found the culprit...lol

[cruiser54]

Likely so.

What about between engine and trans?

[Car Enthusiast]

What fluid should you put in there?

[cruiser54]

Dot 4 brake fluid

[N8inVT]

After replacing master cylinder, we gravity bled, and then pumped. Had firm pedel, next day pedel was gone. No leaks between engine and tranny. Today we have been bleeding and getting some air. We pump slowly, close bleeder, let off clutch, repeat. can't seem to get clutch and its still pushing out air. Line was replaced with cylinder. Is this a long proccess for bleeding, or is the clutch bad, maybe a shift finger/fork?.

[Pete M]

did you bench-bleed the master?

[N8inVT]

5 minutes ago, Pete M said:

did you bench-bleed the master?

Yes

 

[cruiser54]

Pump the pedal about 40 times and walk away. See what happens after 20 minutes.

[N8inVT]

15 hours ago, cruiser54 said:

Pump the pedal about 40 times and walk away. See what happens after 20 minutes.

Did this, doesnt seem to do much. No leaking between engine and tranny, we re bled last night, gravity bleed, had firm pedel again, drove around fine, shifted good. Parked at 9.00pm and by 7:00am no pedel. I don't think its the slave, but we can't figure out where we are getting air from, or why the slave isnt leaking fluid if its bad. don't want to do slave and new clutch just to find out we still can't get it to bleed right, and keep pedel.

[cruiser54]

AFTER it has been bled and you have a good pedal, do the 40 pumps. 

 

You may have gotten a faulty master cylinder, but they tend to leak into the cab. 

 

Is the rubber hose original? 

[RuDawgAmus Prime]

On 6/30/2022 at 4:07 AM, N8inVT said:

Check your pedal. Mine had the same issue replace the clutch master cylinder, didn't help. Found a video where a guy had a bent side ways and bent back clutch pedal. Same issue with mine except mine had a broken weld. Long story short straightened and rewelded my pedal. Painted. And installed. Shifts better and easier than ever. What the issue was in the arm that comes out of the clutch master cylinder to the medal was not being able to do it's full "extend and pull back" it was just barely moving. Now 3 weeks later my truck shifts perfectly after the repair. It's worth the 10 minutes of taking the pedal off to check.

 

 

Did this, doesnt seem to do much. No leaking between engine and tranny, we re bled last night, gravity bleed, had firm pedel again, drove around fine, shifted good. Parked at 9.00pm and by 7:00am no pedel. I don't think its the slave, but we can't figure out where we are getting air from, or why the slave isnt leaking fluid if its bad. don't want to do slave and new clutch just to find out we still can't get it to bleed right, and keep pedel.