I ran my rear diff breather up along the fuel tank filler hose and wire tied it in place there behind the filler port. Why drill through the filler port plate?

 

So there's less likely of a chance that dirt and debris will git clogged up in the breather and you can easily access it to check/clean it. With it along the fuel hose, you'll have to undo the tie in order to check/clean it and it will be exposed to the dirt that's flying up under there.

 

I'm thinking about doing this mod. I'm wondering what are the benefits of doing this? and what about the front diff breather valve?

 

The benefit is that you don't have to worry about water being sucked into the differential or if yer stock breather valve sticks...you don't blow gear oil out yer axle seals...thus ruining the rear brake shoes and yer day.

Believe it or not...the front differential already has a factory breather mod!

 

thanks bam for the info. this is how the front breather looks in my truck, is that what the factory breather mod look like??

 

Hmmm...I was under the impression that the front differential already had the breather up on the firewall. I guess it doesn't.

So you'll have to do one fer the front differential as well. Maybe it was the Hilux/Pickup/4Runner vehicles that had the front breather already set on the firewall from the factory.

 

BZP,

I got around to doing this on my truck. I followed the same recipe, except that I also did the front diff. This one is a little tricky, because there is only about 3/4" of space between the breather and the bottom of the oil pan. I shortened the breather hose connector to about 1/2" long and made it bend about 30 degrees. I did this by slicing out the middle section of tubing and TIG welding the two ends back together. Now it _just barely_ fits up there without kinking the hose.

I think the "right" way to do this would be to find a male-to-female 90 degree connector, so that you could screw it into the diff and then attach the hose barb from the side. Unfortunately, the thread isn't NPT. It looks to be BSP (like the oil sender) but I didn't check it with a thread gauge.

Here are some pics:

Anyone know of a source for BSP fittings?


Arclight

 

This thread has been dormant for a long time. I am going to go ahead with the rear breather mod, and I would love to do the front as well. Unfortunately, I am not a welder, so I would need to source a 90-degree BSP fitting like @arclight23 mentioned 10 years ago.

Huge kudos to anyone who has an off-the-self suggestion!

 

I used push-to-fit fittings and airline to replicate a “poor man’s” version of the ARB differential breather kit. I sourced all the fittings and airline on Amazon.

This is the 8mm air tubing I used:
uxcell Pneumatic Air Tubing, 8mm OD x 5mm ID 15m(49.2ft) PU Polyurethane Air Compressor Tubing Hose Pipe Blue

I used this 90-degree fitting for the front differential and it fit without modification:
Metalwork Plastic & Nickel Plated Brass Push to Connect L Shaped 90 Degree Elbow Male Fitting, 8mm OD x 1/8" NPT Male (Pack of 2)
I also used one of these 90-degree fittings for my transfer case.

I used a straight fitting for the rear differential. I bought a 10 pack on Amazon for ten bucks or so. They were 8mm Tube x 1/8BSP thread, but I can’t seem to find them on Amazon anymore.

I ran the rear diff vent up and into the fuel filler area. I ran all the other vents up to the firewall. I topped all the relocated vents with one of these little fuel filters that I also got on Amazon.
shiosheng 6pcs 125-527 Fuel Filter 13120507320 13120519830 for Echo String Trimmer/Edger/Backpack Blower

 

What a contributor! Looks like the 90-degree fittings you bought are no longer listed, but I think these 90 Degree Push to Connect Fittings Air Fittings, PL 8MM Tubing Od x 1/8" Npt (or number of other options on Amazon) should work, so I am placing an order now! It is worth a $7 attempt at least

Once they come in, I'll check my local hardware store to see if they have sell some tubing by the foot that'll work for the transfer case and front and rear diffs.

Thank you so much! I am sure someone else will find this useful in the future as well!

 

I just went through my photos and I definitely installed the fitting when the differential was removed and the front cover was off.

Here is a photo with the fitting installed immediately after the differential was finally reinstalled…

(In this photo I had the vent temporarily plugged with a short piece of tubing that I occluded with hot glue, but I replaced this temporary plug with tubing and a filter in the engine compartment before I ever drove it.)

 

That makes waaaayyy more sense! I think I might just be able to get the breather off of the front diff with a shorty 14 wrench and get the 90deg fitting in with a shortly 12.

I may pull the boot off the transfer case selector in the cab to see the case breather better, and if there is a nut on it. Seems more likely that it is pressed as JT mentioned and a breather mod isn't feasible without pulling the whole drivetrain.

I'll update here if I make any progress or findings.

 

Old thread I know but still relevant and super easy. I have Dana 44 up front and it had somewhat of a breather mod already.....hose ran up into the engine bay. Ordered/picked up the items BZP called out added a dorman breather to the hose for the front axle and did then rear toy axle as BZP suggested. Probably 15 mins total.