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Transmission hard lines leak

90xj06

NAXJA Forum User
Location
Peabody, MA
1988 XJ AW4.

I have a leak at the front most fitting on the transmission to the hard line. at the quick disconnect.

is there an oring kit for this. because i pulled it apart once and replaced it with a spare used hard line and that lasted about a month. and now its leaking again.

when i pulled it apart it had 2 orings and a plastic sleeve that fell out. what order does it go?

or is there an easy way to just go with a barbed fitting.
 
The disconnect o-ring set up goes o-ring, spacer, o-ring. You should get new O-rings but keep that spacer. Otherwise, google up "Jeep transmission line connector". You should find the Crown o-ring set AND the plastic clip which will fix your leak for about $8.00 per connector

A similar set-up is used for the fuel lines. The *book* says every time you disconnect the fuel lines you need to replace the O-rings...but I've gotten away with re-using them few times. Possible, but not recommended.
 
So, when you get that kit, you can re-use the plastic clip OR use the new clip. Tear the old plastic clip off the end of the line with some pliers. Slide the new clip on the tube (oriented the same way) until it *clicks* over the shoulder on the tube. Then slide an o-ring on the tube, then the spacer, then the other o-ring. Shine a flashlight into the female connecter of the tranny, make sure there are not any *extra* O-rings or pieces of o-ring inside there. Then take the tube, with the clip, the O-rings and the spacer and shove it into the hole until it clicks. The *ears* should click into the fitting.
 
1988 XJ AW4.

I have a leak at the front most fitting on the transmission to the hard line. at the quick disconnect.
.........
or is there an easy way to just go with a barbed fitting.
What about converting to a barbed fitting? Are the transmission and radiator fittings standard sizes or are adapters needed?
 
A better idea would be to convert to JIC fittings with field-replaceable ends. There is no swage tool needed, the fittings screw right onto the hose.

Granted, the hose is *MASSIVELY* over-rated for the pressure you'll have in the lines (something like 4500PSI, you only have 50 in the lines themselves), but that's not a bad thing. The hose is less than $2/ft. Same stuff they use in forklifts and the like.

I had lots of issues with hardlines fracturing for multiple reasons with my S10. Cost me 3 transmissions. I changed to the JIC -6 stuff and haven't had another problem.
 
Mine tranny lines leaked where the metal line crimped to the rubber hose so I put new lines from napa on mine 98 xj year or so later they were leaking again same place so I cut the metal part out and replaced with tranny cooler hose been two years no leaks.
 
You really need to make sure you flare the lines when you attach rubber hose to hardline. Otherwise, it's not if but when they will come off.
 
so i changed the orings and its still leaking. im wondering if its not leaking from that. it looks to be spraying upwards and everywhere. im going to order some new hardlines
 
I found 2 barbed fittings on Amazon; they're M14x1.5 with a 3/8" nipple. I'll have to check and see if there's enough room at the trans end to make the turn using flex hose. I think it's pretty tight under there...
 
I found 2 barbed fittings on Amazon; they're M14x1.5 with a 3/8" nipple. I'll have to check and see if there's enough room at the trans end to make the turn using flex hose. I think it's pretty tight under there...

I think you'll be fine.

From experience, however, I'd urge you not to depend on the barbed fitting alone. Tranny fluid is a very "high creep" fluid- it's been my experience that barbed fittings WILL leak.

That's why, in situations where I can't use the previously-mentioned hose solution (field serviceable fittings and two-wire hose) such as installing a Magnefine filter inline, I use a Clamptite (find it here, I'm not affiliated with them, etc: https://www.amazon.com/CLT05-Clampt...srs=13109854011&ie=UTF8&qid=1513865587&sr=8-1) with some stainless steel safety wire. It is a very useful bit of kit and should be in every tool bag if you're going out bush. In this application, I put the hose on the barbs (Parker Pushlok) and then add a safety wire clamp with this tool. No leaks!

Back to those fittings- make sure to use some thread sealant on them, and don't overtighten. It's possible to crack the housing on a transmission (a big problem with the 42RE and such in the ZJs) by overtightening. I think the fitting you bought is a straight thread with an o-ring seal, so there is no need to put the gorilla-grip on it.
 
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I cut my hard iines off used some 3/8 tranny cooler hose and 3/8 barb fittings double clamp each hose end no leaks been that way for two years now .
 
As you said, you clamped each one. Twice. That works as well.

Lots of barbs claim to not need any other retention mechanism (Pushlok). That isn't always true- tranny fluid in particular likes to find a way past the barbs.
 
Thanks for the tips, Burntkat. I think you're right in that they have the O-ring seal but I'll definitely use thread sealant too. No strong arm torqueing either.

I'm considering attaching the barb fitting to the original hard line with a short section of hose (with a bubble flare on the hard line). Then finishing off with an in-line filter somewhere near the radiator cooler outlet.
 
Sounds like a damn fine plan.
 
........or is there an easy way to just go with a barbed fitting.
My barb fittings came today, and they are Parker 68HB-6-M114 (port adapters). They are M14x1.5 threads with a 3/8" beaded hose barb connection. The O-ring seal is included.

I'm sure those stock quick-disconnects were designed for ease of assembly at the factory, and not for reliability. I think the hose with clamps modification will be much more durable.
 
Completely agree. Thanks for sharing the specs, as I'm going to be doing the same to my XJs
 
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