Terex TA400 dual cone seal not seating

Looking for anyone who has done done work on the zf axles on the ta400 haul trucks. I'm putting a hub back together had a brake piston seal failure. I have new seals , new brake friction discs.My issue is the dual cone seal on the brake package size with the thicker toric will halfway seat with a seal installer , and deadblow hammer ,but if pressure is applied it will seat fully but once pressure is removed it pops halfway out.I don't know what is happening or what I'm doing wrong I followed the steps in the service manual , my planetary hub part of the seal is seated perfectly fine. Everything is lining up fine it's just the seal on the brake side has so much tension or pressure when you put the hub together , and installed everything and your axle but the hub will stop rotating once you start to tighten it. Any tips , or advice are appreciated.

Seem to recall using windex to help roll that seal in so it would not roll back out. Maybe type in search bar for Toric seals. Been years since I done one, but that is what I recall. Simon C

That was Windex in a can as the alcohol part evaporates in 2 minutes or less. Simon C

Simon C said: That was Windex in a can as the alcohol part evaporates in 2 minutes or less. Simon C Click to expand... My thing is the seal is halfway into the groove it is supposed to sit in am I supposed to seat all the way or is it supposed to sit halfway because muy dual cone on the planetary hub side is completely seated but when I lift it into place I mesh with my friction disc hub spins but when I tighten it down my hub stops spinning I have to torque it to 1400-1600 ft lbs when I get it to 500 ft lbs it locks down hub not longer spins , and I have a gap about the size of the amount seal that is not seated on the brake package side.

Greasyfitting said: My issue is the dual cone seal on the brake package size with the thicker toric will halfway seat with a seal installer , and deadblow hammer ,but if pressure is applied it will seat fully but once pressure is removed it pops halfway out. Click to expand... What procedure does the service manual require.? Any lubricant or similar.?

Greasyfitting said: My thing is the seal is halfway into the groove it is supposed to sit in am I supposed to seat all the way or is it supposed to sit halfway because muy dual cone on the planetary hub side is completely seated but when I lift it into place I mesh with my friction disc hub spins but when I tighten it down my hub stops spinning I have to torque it to 1400-1600 ft lbs when I get it to 500 ft lbs it locks down hub not longer spins , and I have a gap about the size of the amount seal that is not seated on the brake package side. Click to expand... So I am not there, my question is would it turn easier if the toric seal went in further. So is it the inner lock that is 1500 Ft lbs or the outside lock that is. Maybe post a picture and myself or someone else might better be able to suggest solution. Could you have a bearing race seat that is not seated. Simon C

Nige said: What procedure does the service manual require.? Any lubricant or similar.? Click to expand... I spoke with rokbak/terex support they said that for dual cone seals they use brake cleaner , or starting fluid and that using a seal installer it should pop into place.

Simon C said: So I am not there, my question is would it turn easier if the toric seal went in further. So is it the inner lock that is 1500 Ft lbs or the outside lock that is. Maybe post a picture and myself or someone else might better be able to suggest solution. Could you have a bearing race seat that is not seated. Simon Click to expand... The side view of the clean hub is now , the side view of the dirty hub is the before disassembly the 3rd pic is the axle slotted nut before removal , the hub had some free play to it like it should before disassembly my thing is I'm not getting that same gap between the hub like original side view that's dirty I shouldve cleaned it in hindsight. I can get more photos tomorrow.

The clean hub sideview photo is with everything on and axle but right hub does not spin anymore

Greasyfitting said: The clean hub sideview photo is with everything on and axle but right hub does not spin anymore Click to expand... And axle is tight but hub does not spin anymore* typo.

Simon C said: So I am not there, my question is would it turn easier if the toric seal went in further. So is it the inner lock that is 1500 Ft lbs or the outside lock that is. Maybe post a picture and myself or someone else might better be able to suggest solution. Could you have a bearing race seat that is not seated. Simon C Click to expand... This is as far as I can get without the seal just popping back out at me.

Does the Toric Ring "roll" as you press the seal inwards with the installer tool, or does it simply slide down the "knurled" ramp in the brake housing.?

Nige said: Does the Toric Ring "roll" as you press the seal inwards with the installer tool, or does it simply slide down the "knurled" ramp in the brake housing.? Click to expand... It will roll towards the backside of the face ring and pop out the backside it almost seat but popped out the backside

Nige said: Does the Toric Ring "roll" as you press the seal inwards with the installer tool, or does it simply slide down the "knurled" ramp in the brake housing.? Click to expand... That's what I got now that's as far as it will go before it pops out the back. It will also cause the axle to not spin when you try to put the planetary hub , and everything back on and tighten the slotted nut down

Is the replacement seal OEM or aftermarket.? How do the Toric Rings compare size-wise to the old seal.?

Nige said: Is the replacement seal OEM or aftermarket.? How do the Toric Rings compare size-wise to the old seal.? Click to expand... OEM terex part same size as the original.

In that case I’m sorry I don’t have any other ideas.

Make sure that the Oring isn't twisted, apply pressure the metal ring and use a plastic, narrow spatula, spoon, or trim tool to walk the Oring inward in stages. At least, that's how do them. And the bore the Oring goes into must be corrosion free.

have you tried to assemble without the seal to confirm it is the problem?

Mark250 said: have you tried to assemble without the seal to confirm it is the problem? Click to expand... Yeah we put it together without the seal, and the gap closes.