1994 4.0 manual YJ not going into gear

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Zach-p21

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Hello there!
I have a Manual 1994 4.0 YJ and I have been having some problems with it lately. When I drive it, it sounds like it’s squealing coming from the clutch or transmission. It also has trouble going into 1st and reverse. I have it taken apart right now and the clutch and throw out looks fine.
Any ideas or suggestions? Thanks!
-Zach
 
Not sure what the squealing is, but the issue getting it into 1st and reverse is usually because the input shaft is turning when it shouldn't be. Clutch not releasing or it also seems to be an issue with high mileage AX15s. Not sure of the exact cause.
 
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My issue with not being able to get into gear has always been master/slave cylinder assembly went bad, but I’ve never had squealing. Squealing would have me thinking throwout bearing.
 
Does it squeal all the time or only when shifting? I've had throwouts go bad and grind but they were a different kind with a carbon ring, not the ball bearing type and only made the noise when depressing the clutch.

Bad synchros are somewhat common in 1st and 2nd gear. Reverse has no synchro so it grinds most of the time. I always put it into 2nd gear before reverse to stop the cluster from rotating.
 
a new master cylinder and slave is first.
the slave must stroke far enough and push the TOB to release the PP (pressure plate or the trans will grind or BALK)
always assume the cheap and near zero labor parts are bad first. always. I never pull any trans on a guess. ever.

my 95 (and i think all 94) have the slave on left side of bell housing, and mine was bad.
$100 preprimed set and its istalled in 30minutes ,no need to pull the tranny and transfer case.

when you push the clutch pedal by hand and feel it, and it is soft/weak and then you feel it tighten up, late in the travel, a new master /slave is first
yes a collapsed TOB or burned up PP fingers will make it fail, bad TOB most times wrecks the PP spring fingers. (they get annealed too hot...)
as will disc warped or cracked or PP plate warped or PP springs cracked and or warped, the clutch will drag. yes.

TOB means throw out bearing
this clutch automatically sets zero play in the travel end to end and TOB to PP . there is no play here. (like seen on cable clutches)
one more clue
if you install the slave to studs and you get no 1 full inch of preload,(felt) there will be no working clutch.
good luck .
seen many replace the whole clutch(in the bell) and all and the slave was bad only.
endless posts on line like that.

to bleed it ask, I have trick.

ok found the edit button, sorry for double post.
 
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Dorf said:
a new master cylinder and slave is first.
the slave must stroke far enough and push the TOB to release the PP (pressure plate or the trans will grind or BALK)
always assume the cheap and near zero labor parts are bad first. always. I never pull any trans on a guess. ever.

my 95 (and i think all 94) have the slave on left side of bell housing, and mine was bad.
$100 preprimed set and its installed in 30minutes ,no need to pull the tranny and transfer case.

when you push the clutch pedal by hand and feel it, and it is soft/weak and then you feel it tighten up, late in the travel, a new master /slave is first
yes a collapsed TOB or burned up PP fingers will make it fail, bad TOB most times wrecks the PP spring fingers. (they get annealed too hot...)
as will disc warped or cracked or PP plate warped or PP springs cracked and or warped, the clutch will drag. yes.

TOB means throw out bearing
this clutch automatically sets zero play in the travel end to end and TOB to PP . there is no play here. (like seen on cable clutches)
one more clue
if you install the slave to studs and you get no 1 full inch of preload,(felt) there will be no working clutch.
good luck .
seen many replace the whole clutch(in the bell) and all and the slave was bad only.
endless posts on line like that.

to bleed it ask, I have trick.
Click to expand...
more... the reverse gear is the (COAL miner) canary gear.
it is the first to grind if the clutch does not fully release,(drags) so that is all I need to know,... and it does.

the slave can suck in air , when bad (it's piston seals died, as they all do old)
and leaks too, but never seen as it leaks to the ground UNSEEN, only when driving and shifting
the MC will leak down the fire wall, either or both sides. (witness it)
 
just did mine and now the clutch has full pedal. (a 1hr fix, not 20hours)
new , mc/slave set ready to install.
it had (SLAVE ,inserted act1) 1" full inch of preload (felt resistance) at the slave, so the clutch was good.(and must be indexed to the yoke pit left end. or fails)
I now have factory quality clutch at the left foot. ( big grin ,happy as a clam)
never blame the clutch first. I've had like 10 bad slaves in 59 years on the road. (all work mine)
I do hope I saved you 20 hours of labor and $300 in parts and $2000 in labor.

the TOB is a high quality ball bearing not some old VW carbon ring jive.
we can not hear that squeal.

lots more, the tranny can fail if GL4 not clean and at spec level. the bearings will fail if not doing service on time.
if squeal is grinding gears tell that is the clutch of reverse fail;s it is the clutch failing, unheard by me that sound
the MC/SLAVE is first. when reverse grinds this is first
 
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