AX5 Vent Discovered

**Feetwet** · 01-25-2009, 02:15 PM

The 5 threads that you get searching "AX5 Vent" were inconclusive. Some guys even claimed the AX5 had no vent.

The FSM does not address this. After my last submarine adventures on the trail I changed all my fluids and got a nice milkshake out of the transmission. Time to deal. I pulled the shift boot and cover plate and sure enough, there it is on the front of the shift tower. Some Jeeps evidently have a hose installed but my rig just has a little metal breather cap.

Sorry paint job, I know...

Anyway, the job now is to get that cap off and install a hose leading up into the engine bay. The cap spins freely but doesn't seem to want to come off. Has anyone here done this fix? What's holding the cap on? Is the fitting underneath usable as a hose mount?

Your input is encouraged, I'll post the eventual results.

kloppk · 01-25-2009, 02:44 PM

I'd pop the 4 bolts and yank the shift tower off and look at it.
You'll have to loosen the tcase shifter assy an move it out of the way to get the 4th bolt out.
Your vent may be a press fit or screwed in.
Just find a way to pry/pop/unscrew it and then put a brass barbed fitting
in the hole (you may have to tap it) and then run your vent line up the firewall.

I did this to my AX-15. It had no vent to start with. I just drilled and tapped
a hole for the brass barb fitting.

**Feetwet** · 01-25-2009, 03:47 PM

Quote:

Originally Posted by kloppk

I'd pop the 4 bolts and yank the shift tower off and look at it.
You'll have to loosen the tcase shifter assy an move it out of the way to get the 4th bolt out.
Your vent may be a press fit or screwed in.
Just find a way to pry/pop/unscrew it and then put a brass barbed fitting
in the hole (you may have to tap it) and then run your vent line up the firewall.

I did this to my AX-15. It had no vent to start with. I just drilled and tapped
a hole for the brass barb fitting.

So you're saying your AX15 had no factory vent? Why didn't it explode or blow out the seals? I'm not understanding something here....

kloppk · 01-25-2009, 04:20 PM

Quote:

Originally Posted by Feetwet

So you're saying your AX15 had no factory vent? Why didn't it explode or blow out the seals? I'm not understanding something here....

Some AX-15's were just "vented" by way of the rubber boot around the shifter.
It's not a tight seal so air if needed could make it's way in and out of the top of the tranny.

When I installed my vent hose I sealed up around the shifter boot with RTV to keep water out.

**trw** · 01-25-2009, 04:24 PM

Quote:

Originally Posted by Feetwet

So you're saying your AX15 had no factory vent? Why didn't it explode or blow out the seals? I'm not understanding something here....

because it vented through the shift tower.

my AX5 had no cap either, anywhere, it also did not have the dust boot around the shift stub shaft, and that was just a gaping hole letting water in left and right until the bearings inside went south.

I remember someone posted a thread where they extended their vent and also sealed the shift tower using a universal rack and pinion boot purchased at Autozone ziptied in to stop water from entering under the dust boot (I got this same boot at Autozone, I just haven't been able to install it yet)

my new AX15 has a vent cap this time, so I will be performing this same mod soon, along with the boot for the shift tower.

**Feetwet** · 01-25-2009, 04:39 PM

Gotcha. So you had to seal up the shift tower openings then run your own vent in order to extend it.

That's good for the AX15...Anyone modified the breather cap on the AX5?

**Feetwet** · 01-26-2009, 05:49 AM

Well, I'm gonna bite the bullet go for it. I hope I don't break anything.....

I'll post up the fix If I in fact fix it.

**Feetwet** · 01-29-2009, 05:20 PM

Went to Advance Auto and bought a 3/16" vacuum elbow, 6' of 3/16" vacuum hose and a 1" hose clamp. Total cost about $8.00. I had some zip ties and RTV laying around.

Remove the fasteners from the shift boot and tunnel cover plate. No need to completely remove them, just rotate them around a bit and up out of the way. I tied them off to the steering wheel. Locate the breather cap at the front top of the shift tower.

Use a pair of pliers on the top of the metal cap. Gently rock it back and forth while pulling upward. The cap will pop off and leave the vent exposed. There's a spring and rubber washer inside the cap. Discard these three parts.

The barb on the new fitting is just a bit too big. A little sandpaper on one leg makes a perfect fit. This leg will go in the vent hole.

Apply a thin bead of RTV to the sanded leg and press it firmly into the vent hole. Point the fitting toward the left front tire so the hose will clear everything.

Attach hose and clamp securely. Route the hose over to the frame rail, forward and up the firewall, using zip ties as you go. I followed the fuel return line up into the engine bay. Make sure the hose clears any hot or moving parts, of course.

Make a couple loops and fasten up high. I used a handy wire loom clamp to tie to. You can add a check valve to the hose end if you choose.

That's it. Button up the shift console and you're on your way.

**YJake** · 02-10-2009, 11:58 AM

Excellent!

I should really do this to my AX5. As soon as I get my paycheck I'm going to get the hose, attachment, silicon, and start

**CrawlingForward** · 03-18-2010, 12:25 PM

This is a great tutorial! I suspect it's one of the reasons why AX5 started to go downhill fast once it hit New England. This is definitely on my agenda for the summer! Thanks so much!

**Feetwet** · 03-19-2010, 08:02 AM

I'm glad you guys found this useful. I've been in a lot of water in the last 18 months hunting and fishing and have had no water in my AX5. Floorboards have been soaked but not my tranny fluid......

**Andywear** · 07-07-2011, 02:09 PM

Thanks for putting this thread in the FAQ.

Planing on doing this weekend along with Trans oil.
My AX5 has no breather vent, Just some info.

**Opihi59** · 07-07-2011, 04:01 PM

Quote:

Originally Posted by Andywear

Thanks for putting this thread in the FAQ.

Planing on doing this weekend along with Trans oil.
My AX5 has no breather vent, Just some info.

You could drill out that "boss" area to the appropriate size and then tap it with 1/8 NPT tap (National Pipe thread) you can then get a brass fitting, barb or smooth on one end, and 1/8 NPT on the other end, thread that in and slip your breather line on that if you feel you need one.

Below is a photo of this type device I used in another application.

**Andywear** · 07-07-2011, 04:15 PM

ight, I probly dont need one but... I was just going to drill a small hole on that top plate where the shifter goes stick in the elbow and then RTV it. but guess i should figure out how to

Quote:

seal the shift tower using a universal rack and pinion boot purchased at Autozone ziptied in to stop water from entering under the dust boot

then i would actually have a reason to fab this breather tube up.