Hard to get into 1st gear from a stop

I installed a LUK clutch kit, Timken TOB and a new master/slave in my '98 XJ w/ AX-15. The synchro's were on the way out in 1st gear; it wouldn't fully engage and periodically 1st gear would just pop out of gear when starting from a stop. I tried Redline in the transmission for a year or so, but didn't help. The only thing that helped to smooth the shifting other than double clutching was to add Penzoil Synchromesh gear lube.
As others have posted.... the AX-15 is known to have shifting problems as the mileage accumulates.
 
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jodomcfrodo said:
Reverse is grinding because you don't have a synchro for the reverse gear. You have to wait for the transmission to spin down to shift into it.
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Novak conversions says "The AX15 is fully synchronized in all gears" doesn't that mean reverse too? If there aren't syncros on reverse it is trivial to see if the clutch isn't disengaging, you just push in on the clutch and gently ease it into reverse, it'll grind if it's dragging. I thought this wouldn't work on a Jeep because they all have syncros on reverse?
 
pagrey said:
Novak conversions says "The AX15 is fully synchronized in all gears" doesn't that mean reverse too? If there aren't syncros on reverse it is trivial to see if the clutch isn't disengaging, you just push in on the clutch and gently ease it into reverse, it'll grind if it's dragging. I thought this wouldn't work on a Jeep because they all have syncros on reverse?
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I’m almost 100% sure the AX15 doesn’t have a reverse synchro but I’m relying on my memory of forum readings over the years. I know the NV3550 has a reverse synchro, don’t think the AX15 does.
 
I’ve always been in the habit of shifting into 3rd before shifting into 1st or reverse while at a stop on every manual transmission I’ve ever had. It worked in my first car 20 years ago and it’s a habit that’s stuck with me ever since. Give it a shot.
 
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Rubicon John said:
I’ve always been in the habit of shifting into 3rd before shifting into 1st or reverse while at a stop on every manual transmission I’ve ever had. It worked in my first car 20 years ago and it’s a habit that’s stuck with me ever since. Give it a shot.
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Truth, it does work. And at full stop, I sometimes go into 2nd then into 1st. Hasn’t failed me.
 
I drained mine and went to redline recommended by the forum.Mine is the 2000 with the 3550.It had brass in it so I am sure the syncros are on there way out. I have only had it 8000 miles and it is high mileage. It took 1000 miles but it did help.Going between 1st and second takes time.Guess it is normal.Give the new oil a little time.
 
Used to be a syncro was never used in 1st gear. So when they started getting one the wording was that it had syncros in all gears. The thought of a syncro in reverse was absurd back then. This was back when they didn't have to say it had a standard transmission because, well, it was standard. And a 3 speed. Then when auto trans started getting used they began adding more gearing to the gearbox. The auto trannies had a column shift because back in the day they used a column shifter for a manual trans (3 on the tree). When 4 speeds started showing up it went to a floor shift because the complexity of having all that linkage on the steering column.
 
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Swapped out the Master/slave cylinder today and the problem is still there. I'm going to drive it more to let the fluid get a chance to work, but looks like the problem might be somewhere in the clutch/bell housing.
 
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Update: Brought it to a shop to get the clutch replaced and its way better now. It's noticeably easier to put it in 1st at a stop, but the 2nd gear notchiness is still there. Probably the synchros getting a bit worn.
 
Just bought a ‘99 TJ a few weeks ago. Never grinds, clutch is responsive, but has a HELL OF A time shifting into 1st and 2nd. Have had to strategically position in my driveway and park in 1st. If not there is no chance. Have had to start in...3rd several times. After driving about 50-75 miles in a day though it will shift through all 5 gears like butter.

I’ve talked with several mechanics and the TJ is actually on vacation at a shop having a new trans/clutch put in. She had 165k on her when I bought it - I figure we should just start fresh.
 
Having the exact same problem Racecar825 described in his original post, sometimes will not want to get into first gear. I had to check that I wasn't the one who wrote it!

I've put in Redline MT
I've changed out master/slave clutch cylinder (pre-filled so I don't think air bubbles are a problem).

When I start the car it is usually fine for a while, but then inevitably it starts acting up again. It also shifts fine if I shut the car off and turn it right back on. Usually I can shift into another gear and then it will have no problem shifting into first, HOWEVER sometimes even that won't work and then I get stuck at the light, people getting annoyed and honking...

@TrueTexas you mentioned your AX15 input shaft seal was leaking and the fluid was running down the front bearing cover tube and being slung onto the clutch. Would you please explain why fluid on a clutch would cause hard shifting? I'm trying to understand because I am wondering if that is my problem too. Thank you!

@Jerry Bransford I could swear I've met you before or seen your picture somewhere. It's really driving me nuts. Are you a private pilot in the Bay Area by any chance?
 
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g.hayduke said:
With that mileage and the symptoms you describe, I agree with your diagnosis that the clutch is probably not fully disengaging.

Not sure if this works on a TJ but try pumping the clutch pedal a few times before going into 1st like you might pump the brakes if your brake master cylinder was failing.

If that helps, I would replace your master/slave cylinders as that is probably where the problem is. Otherwise, maybe time for a new clutch.
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Random here I just replaced my master slave cylinder and am still having the problem
 
@babyjeep did you ever get this figured out?

The tranny oil front the front seal leak was coating the clutch and flywheel. Best I could tell, when it warmed up, it would allow them to release so the tranny wasn't able to spin down, allowing me to shift. Haven't had a problem since fixing the seal and replacing the clutch
 
TrueTexas said:
@babyjeep did you ever get this figured out?

The tranny oil front the front seal leak was coating the clutch and flywheel. Best I could tell, when it warmed up, it would allow them to release so the tranny wasn't able to spin down, allowing me to shift. Haven't had a problem since fixing the seal and replacing the clutch
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@TrueTexas sorry I did not notice this before. I have not exactly figured it out. I've just been tolerating it. I find that if I very consciously push the clutch to the floor and then slowly shift and wiggle the shifter a bit it works nearly all the time. The few times it won't I just get really annoyed and get honked at, and it works eventually...

What is the "front seal leak" ... I am aware of engine rear seal but what do you mean by "front seal" - where is it located? I do not see leaking fluid under the vehicle.

Thank you!
 
racecar825 said:
Recently bought a 1998 TJ Sahara with 163000 miles. Sometimes it is hard to get into first from a stop. It it takes a firm pressure to get it in, 2nd gear is a bit notchy but fine otherwise, 3rd to 5th are as smooth as butter. It's still driveable, but sometimes i worry i won't be able to get it into gear at a red light. I changed the transmission fluid to Redline MT-90 about 100 miles ago and it feels like it got slightly better, but the problem is still there.

Symptoms:
  1. Seems like it happens after driving a bit and the Jeep warms up.
  2. If I put it into 1st while rolling at ~2-3 mph, it slides right in without any problem.
  3. sometimes it grinds into reverse when at a stop
  4. I can go through all the gears with the engine stopped, no problem

This leads me to believe that the clutch isn't fully disengaging and keeping the the input shaft of the tranny slightly spinning, but i could be wrong.

After reading a lot about this issue, some people say the synchros on the AX-15 are known to go bad. Some people have replaced the slave/master cylinder and the problem goes away. I just ordered the LUK pre-filled master/slave assembly. Hopefully that fixes the problem. Has anyone else had this problem?
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I haven't read all the comments, but I will add my experience since it is similar. I have the NV3550 so keep that in mind.

When I got the Jeep in 2015 I noticed the same things you describe and thought something was wrong with my transmission and/or clutch. I tried different fluids. Ultimately Royal Purple worked the best. But what really helped is before trying to put it in reverse or first, put it in 4th. Keep the clutch pedal down and put it in 4th, then the gear you want to go into. I almost always do this before putting it in reverse, and for first gear I have developed a sense of when I will need to do this or not.

As for 2nd gear, same thing as you. What works for me is to shift slowly. Bring the shifter close to second, leave it there a moment, and I will feel a little "catch" and know it's ready to go in.

I've been doing the above since 2015 and haven't needed any transmission or clutch work in that time, and I don't know when any of that may have been done in the past by the PO.

Somewhere in there I added rev matching and double clutching to the mix when I feel like it, but it isn't necessary.

Hope that helps... not saying you don't have any issues that need fixed, but maybe your situation is like mine and it just needs driven differently than, say, a Honda Civic (talk about easy mode stick shift! lol).
 
I had the same symptoms. Replaced master/slave with a pre-bled kit and the disengagement problem went away.
 
I’ve always been in the habit of shifting into 3rd before shifting into 1st or reverse while at a stop on every manual transmission I’ve ever had. It worked in my first car 20 years ago and it’s a habit that’s stuck with me ever since. Give it a shot.

I have been shift into second then into first for over 50 years, a habit learned from driving non synchro transmissions.
 
Pilot bearing swap fixed mine ...had same issue 1st and reverse but mine was fine when start her up till bit of warmth gets into engine then pow less turn motor off or go into 4th first couldn't get first or reverse
 
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