Hmm maybe synethic motor oil will help mine...

FYI, I had an issue with the clutch catching at the bottom of the stroke and usually the carpet got in the way from full disconnection, caused gears to grind, not fun to drive ect. This i believe is from non-OEM clutch, wrong adjustment of ball screw, machining the flywheel or just the stars not being aligned. Well I simply made a little bit longer push rod for the slave, took some adjustment to get perfect but now the pedal engages in the middle of the stroke like it should.

 

With the engine off it shifts smooth. Nothing is leaking. Will I cause more damage if I just wait until the issue gets worse?

 

My 99 does the same thing into second especially if its cold, and i have no lift all stock suspension.. what do you recommend the problem is in my situation?

 

My AX 15 does the same for second. When it is cold I find it much easier to slip into second around 5-8 mph...after a while it works per usual.

But then again I also have the problem of shifting into any gear after slipping it into neutral and then letting the clutch go after sitting in an hour or two of traffic. I would then have to kill the engine put it in gear and start her up....needless to say the clutch foot gets heavy. I replaced the master and slave so it looks like it is probably the clutch.

I'm running 10w-30 if that matters

 

^ ya sounds like the TOB has worn into the diaphragm spring a little. Just replaced the clutch on my wife's Miata for the same reason.

I'm telling you guys, run that Amsoil 75-90 GL4. It's just that good. I run it in all my vehicles (97 XJ, 91 Miata, 62 Unimog, 500hp 96 240sx, 98 altima)

 

then its a clutch problem, sounds like its not fully disengaging.
could be caused by the slave or master cylinder as well as people have been mentioning.

 

How hard is it to replace the master and slave cylinders? It for sure is not releasing all of the way. Its popping in between gears and really hard to switch gears.

 

Not necessarily. I just replaced the clutch on my wife's Miata and the problem there was a worn diaphragm spring on the pressure plate; which prevented the clutch from completely disengaging. We couldn't even start the car with the clutch in, engaged in a gear; it would lurch forward. It also wouldn't "shift smoothly", as the OP describes, when it was off. So having said that, I still feel its not related to the clutch. It also wouldn't be gear selective.

 

Here's my experience with my '96 with 187000 miles on it:

1) For a nearly effortless shift from 1st to 2nd (it is possible!), I have to rev up to at least 2k rpm, smoothly pull the lever into neutral for just a moment and then smoothly continue into 2nd. When done 'correctly', it's easy-sneezy with just a smidgen of resistance.

2) Done any other way and it will either hanging in neutral and just not go into 2nd or will go if I gently muscle it. There's some silent obstructions that can be felt but there is no gear noise or grind from any clutch disengagement, since i can slip it right into third if necessary.

Runs quiet and downshifts more easily into 2nd than upshifting. No popping or other issues once it's actually in each gear - just the shifting action. 4WD goes in and out as it should with no mechanical issues or sounds.

I'm curious if the shifter mechanism itself can wear enough to produce this result without affecting the actual gear train...

 

What other problems could make the clutch not fully disengage?

 

my 90 had the same problem. changed clutch, master and slave. still hard shifting. went to pennzoil synchromesh and it shifts like butter...even spent $100 on stainless braided clutch line. better pedal feel than the rubber wrapped stocker...fyi

 

My 97 had the same trouble. Don't waste the money getting the case looked at. I'd try the Amsoil like Unimog said. Maybe throw a little money like previous poster said as well. I don't know what your town is like for transmission rebuilds. I got mine rebuilt for not having a 1st gear and paid like 1700 on a rebuild. Quadratec sells a brand new AX-15 for a 97-99 Wrongler that will fit an XJ for like 1244 or something along those lines. If something occurs down the line that it does need replaced, I'd do that as my rebuild lasted 9 months (warranty expired by then) and I have synchros out now. I will be ordering the new Quadratec AX-15 when money is available so I know it is new and not a crappy rebuild job.

 

My 95love has the same issue, it quickly pops as I try to take her into 2nd I noticed if I shift at 2k and wait a slight second it slips right in, when its cold its the worst, I also sometimes forget im driving a 95I and shift like I have a sports car dosnt help any

 

Well, I went down to the Jeep dealer a few weeks ago.Apparently there was a recall or something of that sort. They now say not to use gear oil and to use 10w-30 motor oil. I know lots of you guys already said this. So i got some Mobile One synthetic motor oil. At first it was not a huge diffidence. Now after about 500 miles it is shifting much better. No clutch problems or anything of that sort.