Axle fluid level in reference to surface mount of third member...?

[thordehr]

Here's a picture of my third member installed in my custom slightly different housing:

The housing does not have a conventional drain. It fills in a tapped hole in the mounting plate of the third member. You can see it off to the right in the picture....

How high should the oil level be to adequately lubricate the 2 1/2 third member? In other words, how far below the mounting surface that a typical 2 1/2 ton third mounts to is the oil topped off to?

 

[Wildchild467]

id say look in the fill hole of a stock deuce and see where it lines up on the ring gear and go from there. maybe add more to your axle as long as it does not leak out your axle seals. just a thought. if your housing is bigger, might be looking at more than 6 quarts like a stock deuce.

 

[tie6044]

Did you make that housing? What shafts are you using?

 

[thordehr]

Scott, yes, they're custom housings. 4-inch-diameter 0.500-wall chrome-moly axletubes that bolt on to a 1/2" chrome-moly plate center housing. The centersections are the 2 ½-ton military centers with Detroit Lockers and the original 6.72 gears. The outers of both axles are F-450 components including the big calipers, rotors, and bearing hubs. Inside are CTM 300M shafts with removable billet chrome-moly yokes. The stub axles / removable yokes slide directly into 40 spline bearing hubs so there are no locking hubs or drivers. The U-joints are the big CTMs.

WildChild or anyone else out there. I don't have access to a stock axle housing around here, but could I ask a couple of you to look at the axle bolt / stud plate that the center section is lowered down onto on your axle and then look to where your oil level is and take a measurement between the two.

Example here...:

My axle does not have a drain or a side fill plug in order to keep them from being damaged against rocks. Mine is top filled like you can see in the photo. If I can get a good measurement from you all, I can make myself a dipstick and be sure that I have an adequate oil bath.

Thanks all.

 

[thordehr]

Scott, yes, they're custom housings. 4-inch-diameter 0.500-wall chrome-moly axletubes that bolt on to a 1/2" chrome-moly plate center housing. The centersections are the 2 ½-ton military centers with Detroit Lockers and the original 6.72 gears. The outers of both axles are F-450 components including the big calipers, rotors, and bearing hubs. Inside are CTM 300M shafts with removable billet chrome-moly yokes. The stub axles / removable yokes slide directly into 40 spline bearing hubs so there are no locking hubs or drivers. The U-joints are the big CTMs.

WildChild or anyone else out there. I don't have access to a stock axle housing around here, but could I ask a couple of you to look at the axle bolt / stud plate that the center section is lowered down onto on your axle and then look to where your oil level is and take a measurement between the two.

Example here...:

My axle does not have a drain or a side fill plug in order to keep them from being damaged against rocks. Mine is top filled like you can see in the photo. If I can get a good measurement from you all, I can make myself a dipstick and be sure that I have an adequate oil bath.

Thanks all.

 

[gimpyrobb]

From the mounting surface BOTTOM to the bottom of the gear is about 8.5 inches. I would make sure the gear is submerged an inch or so and call it good.

 

[thordehr]

Thanks, I'm guessing if the ring gear is submerged, it will bring oil up to everything else.

 

[gimpyrobb]

Yup, thats the way I see it.

 

[Jake0147]

It's ten thirty at night. It's raining. There's coyotes out there. I hope you appreciate this... It's uphill both ways.

Top of the axle housing to the bottom of the fill plug threads is 4 and one quarter inches. A little proud of that actually, but not quite four and five eights.

General consensus among trustworthy folks is that this is the "high" mark, and one knuckle below that (three fourths to one inch) would be the "low" mark, with a preference towards keeping the level towards the lower side of that window.
Consider that as a guideline. Changing the shape and volume can and will affect how the oil reacts as the gear moves through it especially at higher speeds. Maybe for the worse, maybe even for the better.., So if you believe you have cause to suspect that it's foaming, leaking too much or too easily, taking pinion bearings faster than it should (and you can expect that now and then...) or any other nuance that may turn up, then I would not hesitate to adjust that level some.

Is the inside of the housing under the drain screw as straight as it looks? Brass plugs are easily machinable (hand drill/tapable). Drill a plug to accept seven (plus or minus) inches of quarter inch threaded rod so as to leave six plus or minus inches in the housing. Drill it just short of breaching the outside, and the taper at the last threads from your tap will "lock" the rod in place. If you wish (or if you choose to drill all the way through) Locktite it in to lock and to seal it. A nyloc nut run up that rod about an inch (measured to your setting) to make a "full mark" based on the plug NOT being screwed in should make for a pretty convenient adjustable dipstick.

 

[gimpyrobb]

Nice Jake! Good thinking.

 

[thordehr]

Hey thanks for that. Didn't see your response and the work that went into it until just now. Thanks though, it's appreciated!

It's ten thirty at night. It's raining. There's coyotes out there. I hope you appreciate this... It's uphill both ways.

Top of the axle housing to the bottom of the fill plug threads is 4 and one quarter inches. A little proud of that actually, but not quite four and five eights.

General consensus among trustworthy folks is that this is the "high" mark, and one knuckle below that (three fourths to one inch) would be the "low" mark, with a preference towards keeping the level towards the lower side of that window.
Consider that as a guideline. Changing the shape and volume can and will affect how the oil reacts as the gear moves through it especially at higher speeds. Maybe for the worse, maybe even for the better.., So if you believe you have cause to suspect that it's foaming, leaking too much or too easily, taking pinion bearings faster than it should (and you can expect that now and then...) or any other nuance that may turn up, then I would not hesitate to adjust that level some.

Is the inside of the housing under the drain screw as straight as it looks? Brass plugs are easily machinable (hand drill/tapable). Drill a plug to accept seven (plus or minus) inches of quarter inch threaded rod so as to leave six plus or minus inches in the housing. Drill it just short of breaching the outside, and the taper at the last threads from your tap will "lock" the rod in place. If you wish (or if you choose to drill all the way through) Locktite it in to lock and to seal it. A nyloc nut run up that rod about an inch (measured to your setting) to make a "full mark" based on the plug NOT being screwed in should make for a pretty convenient adjustable dipstick.

 

[1 Patriot-of-many]

Here's a picture of my third member installed in my custom slightly different housing:

The housing does not have a conventional drain. It fills in a tapped hole in the mounting plate of the third member. You can see it off to the right in the picture....

How high should the oil level be to adequately lubricate the 2 1/2 third member? In other words, how far below the mounting surface that a typical 2 1/2 ton third mounts to is the oil topped off to?

You need to start a thread on how to replace torque rods if you can't buy the regular ones! What are they made of and how did you make them? Pretty wild!

 

[thordehr]

The rods are 2" OD 1" ID. Kinda beefy.

The housings are 1/2" Chrome Moly plate, 4" tube 1/2" wall CM with CNC machined mounting plates. Only set of these axles made.