The other day, when I went to replace my rear brake pads, I found oil *everywhere* under the back of the truck. Complete mess. Seems to be the pinion seal. I dumped a quart of gear oil into the diff and it didn't fill it. I just got back from about a 3000 mile road trip in the truck. No noise, but I have no idea how low it's been for how long
Picked up the new seal (90311-38047) and nut (90179-22016 - DON'T BUY THIS, more in a bit) parts at the Toyota dealership yesterday, and went at it today.
Everything came apart fine. But the oil looks bad. Water contamination? Last time I was through water up to the hubs would have been December 2022.
The nut holding the companion flange (which are still available from Toyota for about $240 - I asked) is staked to the shaft, so should be replaced.
I pulled the oil slinger out and looked at the bearing. Seems ok, but you can't see much. I'm guessing that, based on the oil level and the condition of the oil, its days are probably numbered
I found a piece of pipe the right size to tack up a quick seal driver and got that in, put the flange back on. And then the problem. The new pinion nut was clearly not going to thread onto the shaft far enough to stake it. The flange was definitely fully seated. So I compared the new nut (center) with the old nut (left)
The new nut is clearly much taller, flanged, etc. The height that you need to stake it at is in the hex part of the nut. Clearly not going to happen.
So, my quick project is not going to be quick after all - Murphy always gets a vote. Back to the dealership to see if they gave me the wrong part.
The guy at the parts counter double checks the part number, and checks across years (my axles are out of a newer truck). The part number is right - but it superseded the original part at some point. But it clearly won't work and the original part is no longer available. He admired the problem, but couldn't offer any solution.
So, I headed south to Red Line Land Cruisers (Parts, Service - Toyota FJ40, FJ55, FJ60, FJ62, FJ80 - https://redlinelandcruisers.com) to see if they'd run into this and how they handled it. Justin took me back into their parts inventory and found me a solution! Part number 90179-22005 MANUAL TRANSMISSION OUTPUT SHAFT REAR SET. I believe it's from an FJ-60. That's the not on the right in the picture above. It's identical height as the original. The hex part is bigger - took a 1.25" socket, vs 1.1875" for the original (I don't have metric sockets that big, but those fit well).
Put everything back together, and refilled with fresh gear oil. Given how that looked, maybe I'll change it out again in a few hundred miles. But I suspect the damage is done. We'll see.
I did inspect my breather - everything looks intact. I have it extended up behind the fuel fill. I pulled the filter off the end - which is completely caked with mud & dirt - and blew it out while the pinion was apart. I guess my working theory is that on my long road trip, the diff oil got hot enough to boil off the water. The breather filter was to clogged to do its job, so it pushed out the pinion seal instead.
Hope that helps someone. Huge shout out to Justin at Red Line for getting me back on track!
Picked up the new seal (90311-38047) and nut (90179-22016 - DON'T BUY THIS, more in a bit) parts at the Toyota dealership yesterday, and went at it today.
Everything came apart fine. But the oil looks bad. Water contamination? Last time I was through water up to the hubs would have been December 2022.
The nut holding the companion flange (which are still available from Toyota for about $240 - I asked) is staked to the shaft, so should be replaced.
I pulled the oil slinger out and looked at the bearing. Seems ok, but you can't see much. I'm guessing that, based on the oil level and the condition of the oil, its days are probably numbered
I found a piece of pipe the right size to tack up a quick seal driver and got that in, put the flange back on. And then the problem. The new pinion nut was clearly not going to thread onto the shaft far enough to stake it. The flange was definitely fully seated. So I compared the new nut (center) with the old nut (left)
The new nut is clearly much taller, flanged, etc. The height that you need to stake it at is in the hex part of the nut. Clearly not going to happen.
So, my quick project is not going to be quick after all - Murphy always gets a vote. Back to the dealership to see if they gave me the wrong part.
The guy at the parts counter double checks the part number, and checks across years (my axles are out of a newer truck). The part number is right - but it superseded the original part at some point. But it clearly won't work and the original part is no longer available. He admired the problem, but couldn't offer any solution.
So, I headed south to Red Line Land Cruisers (Parts, Service - Toyota FJ40, FJ55, FJ60, FJ62, FJ80 - https://redlinelandcruisers.com) to see if they'd run into this and how they handled it. Justin took me back into their parts inventory and found me a solution! Part number 90179-22005 MANUAL TRANSMISSION OUTPUT SHAFT REAR SET. I believe it's from an FJ-60. That's the not on the right in the picture above. It's identical height as the original. The hex part is bigger - took a 1.25" socket, vs 1.1875" for the original (I don't have metric sockets that big, but those fit well).
Put everything back together, and refilled with fresh gear oil. Given how that looked, maybe I'll change it out again in a few hundred miles. But I suspect the damage is done. We'll see.
I did inspect my breather - everything looks intact. I have it extended up behind the fuel fill. I pulled the filter off the end - which is completely caked with mud & dirt - and blew it out while the pinion was apart. I guess my working theory is that on my long road trip, the diff oil got hot enough to boil off the water. The breather filter was to clogged to do its job, so it pushed out the pinion seal instead.
Hope that helps someone. Huge shout out to Justin at Red Line for getting me back on track!