I have time.... I'll just wait patiently for the story!
Grab your :lurk:
It's a goofy long story alright. My axle has Gonorrhea. Well, the story begins late last March in Death Valley as we were just outside of Furnace Creek on our way up to Scotty's Castle. As we were cruising along up the steep and narrow road a few miles from Scotty's the truck suddenly slowed down like an anchor had just been latched to the bumper. It happened three times very quickly. No wheel lockup but the truck made a quick three step reduction in speed. It was odd, it wasn't like the engine lost power but more like the brakes applied but yet I could tell it wasn't brakes. There was no noise associated with the sudden drag either. Anyway we arrive at Scotty's and I do a quick walk around once we park and discovered the rear axle vent puking its guts out (Hey, Scotty….no charge for repaving your parking lot for you
). There was gear oil everywhere! I thought, okay….it was a long steep climb, so maybe it just got hot. We toured Scotty's then the crew all headed on out into the desert to play for the rest of the week on the trails. We did the Race Track, Lippincott Pass, (and others that I can't remember their names) over the next few days with no issue. Then as we left Panamint Springs in Death Valley on our way to Beatty, NV it did it again. I felt the axle stall 3 quick times and let loose. When we stopped for fuel the axle vent tube was having an orgasm again while squirting gear lube everywhere. Now I am really thinking there is some major heat being generated in the axle as we make those steep climbs. I was also starting to suspect the Autozone house brand gear oil as not up to par for the heat. Although, it's not that hot in DV in late March anyway!
From there it was another 2 days and 1,500 miles to get home and the axle never again stalled or belched oil as we saw toothed our way through Utah and the mountain passes of CO. Once I got home I pulled the cover to have a look around. All looked great with no evidence of overheating at all. I decided to order a HD rear cover that also allows for more fluid capacity. I slapped that on along with some Schaffer Synthetic gear oil (75/90) then a few weeks later we took off for OX13 in Flagstaff. On the way to OX13 when we stopped to visit first coffee return station in Trinidad, CO (90 miles from home) I found the damn axle belched out a ton more oil and coated the entire rear of the camper, fuel cans, water can, etc. I was pissed. This synthetic oil is horrible to clean off! Stinks too!! We mushed on to Flag anyway where it finally stopped puking somewhere between Albuquerque and Flag…finally! It behaved nicely on the way back home as well with no leaking but I never added oil….I just let it go thinking it needed to find its happy spot level on its own.
So last winter while I was redoing the NV4500 I pulled the fill plug on the rear axle and poked my finger in there. I couldn't reach oil so I shined a light in there. Couldn't see oil…..so I poked wire in there and the oil was at least 2 to 3” down from the hole. Umm, that's not right so I let it be until I could open the axle up again. By the time I had time to mess with the rear axle again was about a week before OX14. This time I removed both axle ends suspecting maybe there is a wheel bearing issue. I found nothing but a leaky axle seal on the LH side and the bearing cage on the outer bearing on the RH side was cracked….BUT, there was no real smoking gun as to what caused the two stall episodes in DV and all of the purging of oil out the tube. I went ahead and slapped some new shoes, axle seals and one new bearing & race, sealed it up then hit the road. This time I was a bit wiser….I zip tied a bottle over the vent to catch any oil rather than let it spray all over the back of the camper again.
So, we head out Southbound and down to OX14 and get as far as Alamosa, CO and the 12 oz. bottle is filled to the brim and spilling over. I am like ******!!! I figure okay, the only thing I haven't done recently was to replace the vent hose. I replaced the vent, but not the hose so I stopped by Napa and hosed for nice oil type hose. This time I went ahead and added oil back to the axle. From Alamosa to Farmington, NM it never leaked again, which is a long ride where we were flying along at 70 to 75 MPH most of the way. The next time I looked at the axle vent was when we stopped in Holbrook, AZ and what do I see? Another 12 full oz's of gear oil! Errrrr!!! I just dumped the oil out in there oil bin behind the truck stop and we mushed on.
From there we hung out for the weekend at the Overland Expo then following Monday morning several of us convoyed up to Canyonlands to play for the rest of the week. From Flag to Hite Marina that dang thing continued to belch oil. It is amazing it even had any oil left in the stupid thing so for safe measure I grabbed a few bottles of gear oil in Mexican Hat. Once we arrived at Hite I topped off the axle again then we played in the back country for several days. The next Friday we started heading home and you guessed it, it belched oil all the way home. I just kept stopping ever few hours to dump out the 12 bottle but never added any oil back.
The funny thing is there is no axle noise ever….it is as quite as a church mouse. There also doesn't appear to be any major heat being created as I can touch and hold the axle hub as well as place my palm on the diff cover (I've since purchased a lazar temp gun).
So we get home from OX14 and Canyonlands and this time I'm really pissed and scratching my head. I've been messing with 14 bolts for over 25 years and have never seen anything like this. I pulled the thing completely apart to take a closer look at the ring and pinion, side bearings, pinion bearings, etc. I found the LH axle seal blown this time, the pinion bearing looked okay but not perfect. Same with the side bearings. They are probably as old as the axle is (1976) where they showed some wear but no pitting or bluing or anything else that would be a smoking gun to point to the oil purge problem or why it stalled in DV. I sent the pinion assembly to the local driveline shop to have a new bearing and crush sleeve installed while I replaced every bearing in that axle. All of them got replaced with name brand bearings. Of course, it also got a new set of shoes again because they were so soaked with oil. I also closely measured the oil that went back in (this time I went back to 80W-90 instead of blood thin synthetic) to make sure the oil level was 10mm below the oil fill tube per the service manual.
So with that..I still don't know if it is fixed. It's not like you can just take it for a quick spin around the block to see if it will leak or not. It needs to go on a long ride for a hundred miles or so before it gets fussy. We're going to turn about 400 miles this weekend but they will be low speed mountain highway miles instead of highspeed interstate driving.
I don't believe the axle is getting hot, there is no evidence of overheating. It is like somehow for some reason the axle is building pressure and pushing the oil out. The faster I drive, the faster it will start coming out which would point to a vent problem. The vent is clear and breathable both ways. The only time it belched oil at low speeds was the first time in Death Valley where we were going speed limit (40 MPH) on the road to Scotty's Castle. The other times have been when cruising 75+ MPH. The axle has been in this truck since 1997, Detroit Locker and gears have been in it for a long time as well but this problem started out of the blue. I did add a set of zero rate springs in the rear but it did not change the pinion angle and the pinion angle is fine. If it does it again after replacing every bearing, I'm going to make a boat anchor out of this one and start over with a later model 11.5" AAM axle. I'm sick of the Detroit Locker anyway. I've already spoken to many of the axle go to people in the industry (Stephen Watson at ORD, Randy's Ring and Pinion, Dynatrac and an engineer from Arvin-Meritor through work). They're all scratching their heads too. Time will tell! Open to any ideas if anyone has ran into this one before
Very cool.
