Larry's 1978 K10

[Larry]

I just started going through this thread today and came across this interesting failure. I haven't read further forward in time to see if you eventually solved it, but I have a theory. I'm wondering if somehow the vent tube is loading up with fluid and creating a vacuum and sucking the fluid out rather than the rear end building heat / pressure and pushing it out. It reminds me of my diesel Rabbit that went into a runaway engine mode where it started sucking in engine oil and burning out of control.

Welcome to Expo Venom! Thanks for your interest and thoughts

You know, I am not sure what the hell is going on with that damn rear axle but I am done with messing with it. Again this year it started belching oil out the vent tube about 1.5 hours from home. Because I have trust issues with this damn axle belching oil and making a mess all over the back of the camper I keep a bottle over vent to catch any spray. Well, the 12 oz. bottle was a little over half full after 1.5 hours of driving (~8 oz.). The funny thing is I haven’t added any oil to the axle in 2 years as I figured it may want to find its own happy spot. The other interesting thing is the axle did not purge any more oil the rest of the 1,850-mile trip but we weren't traveling at Interstate speeds anymore after then either. This nonsense has been going on for 3 years now, 2 axle tear downs, 1 complete rebuild (every single piece taken apart, bearings, races, seals, etc. replaced. No culprit found other than one sketchy looking wheel bearing). It will only purge oil when cruising at highway speeds for an extended period of time. Something tells me there is a stack up of tolerances somewhere between the 3:73 carrier, 4:56 thick gear set, Detroit Locker, 35” tires and a hell of a lot of weight over the axle. Rolling that mess down the Interstate at 80-85 MPH seems to really piss off the axle after a while (gas card too, hehe). It does fine on slower roads and off-road. My Suburban has practically the identical powertrain except it weighs a lot less than the K10, different transfercase and it does not have a Detroit Locker and it hasn't ever belched a drop. Funny thing is the K10 didn't either for years then just one day it started and hasn't stopped. None the less, I am done with this axle and not putting another dime or minute of labor in it (other than to remove it from the truck and send it away on Craigslist. It would work fine for a trailer queen Rock Crawler).

A few weeks ago I picked up a pretty clean 94 K1500 with a dead TBI 5.7L for cheap and it just so happens I have a good TBI 5.7L laying around from the Polar Bear Suburban from when it got its 8.1L infusion. So, I am quickly repowering this K1500 for a quick fix and flip then the proceeds will be going to a replacement rear axle for the K10 along with ARB’s front and rear. The rear axle I am planning to use is from a 1995 G-van (same 10.5” axle but in a wider form). I also cannot wait to get rid of the Detroit Locker!!!! Great locker for a dedicated trail rig, but very sucktastic locker for a heavy rig that also travels hundreds of road miles to a trail head. I will never miss the rear steering action of the Detroit Locker that is for sure nor the annoying ratchet… ratchet, clicky clicky, BANG!!! that Detroit’s are known for every time you try to turn or pull away from a stop. Time for selectable lockers!

Here I am changing its diaper and wiping its ******** back in June as we were about 1.5 hours into our week long 1,800 mile Desert Trip.

Desert Trip 2016 trip report HERE. (the trip report not done yet as of today)

 

[Wally'sJimmy]

Hey Larry, love your truck!! It's definitely the reason for my shift into expedition/overlanding rigs. The only time I've seen that happen is when I drove a truck. I was climbing a steep grade at 79K lbs in the summer, at the top of the hill I stopped and the rear-rear axle became old faithful and unloaded all it's fluid. I know that's a totally different situation and easily explained but the only thing that would come to mind in your case is the high driveshaft speed at 80-85 combined with the weight causing the fluid to foam. I definitely understand your frustration, that would drive me nuts.

 

[RedF]

I know it doesnt solve the problem, but have you considered trying one of those accordian type axle vents?

 

[Larry]

Hey Larry, love your truck!! It's definitely the reason for my shift into expedition/overlanding rigs. The only time I've seen that happen is when I drove a truck. I was climbing a steep grade at 79K lbs in the summer, at the top of the hill I stopped and the rear-rear axle became old faithful and unloaded all it's fluid. I know that's a totally different situation and easily explained but the only thing that would come to mind in your case is the high driveshaft speed at 80-85 combined with the weight causing the fluid to foam. I definitely understand your frustration, that would drive me nuts.

Thanks! Yeah, I am starting to think it is a combination of things causing it. The think that kills me is nothing changed....all of a sudden one trip it started belching oil. As mentioned above, the axle even stalled on me a couple times where it actually slowed the truck down like an anchor was dropped from the bumper. Stalling axles are not common in light trucks but you hear of it in big rigs often.

I know it doesnt solve the problem, but have you considered trying one of those accordian type axle vents?

No, I haven’t tried an accordion type vent hose but I have replaced the hose a couple times mounting it in different locations. I really like the idea of an accordion type hose and will go that way when it goes under the knife. Thanks for the suggestion.

The reality is I badly want to get rid of the Detroit locker and given the issues I have had with this axle, $250 to start with a fresh and newer axle (that is a bit wider to match the front track) seems like the best move while I’m at it. The van I am looking to get the axle out of only has 85K on it but of course, it will need to be regeared to 4:56. The van axle also has the big 13” drums which I like. I am not one of the sheaple that buy into the rear disk conversion BS. I like my drums although if a GMT800/900 axle came up (with factory rear disks) for the right price I might consider it. I don’t mind the factory disks but I sure the hell won’t use the Eldo/Toronado calipers like the disk swap kits require. Those calipers weren’t worth the hoot in the cars they came in let alone a big truck. LOL

 

[toddz69]

I don’t mind the factory disks but I sure the hell won’t use the Eldo/Toronado calipers like the disk swap kits require. Those calipers weren’t worth the hoot in the cars they came in let alone a big truck. LOL

Smart man.

Todd Z.

 

[pappawheely]

Smart man.

Todd Z.

I have those on my 14 bolt equipped Blazer. The parking brake is useless.

 

[justcuz]

Somewhere I remember reading about one other guy that had a fluid puking problem with a 14 bolt.
The gear oil foaming would make sense that the bearings were stalling and slowing the truck down.
Even though your going to sell it, let me see if I can find the other posts.

Edit: looking at other posts, I've found everything from too much pinion preload, over tightened used bearings, slightly bent axle housings, cheap gear oil foaming, pinion installed so the oil hole does not line up and gears setup wrong.
One theory was the vent was right above the ring gear and it was splashing enough oil to block any air from entering the case until pressure build up inside forced oil out the vent tube.
If the housing is not getting hot to the touch (where you can't hold your hand on it very long) then it is usually not bearing friction creating heat.
One guy fixed his by moving the vent out to the axle tube. Others have successfully used the bellows type vent.
Hope this provides some food for thought.

 

[xripx]

Larry,

I have an 82 K10 and I'm having a ton of trouble surviving long trips because of the incredibly rough ride. I'll be getting some premium seating, but I'm not sure what to do with my suspension. I'm currently running a 6in Rough Country lift. I saw your suspension setup. Do you have recommendation that doesn't perhaps require and entirely new lift kit? Also, how does your setup feel on corrugated/washboard roads? In my truck, I feel like I'm going to rattle my teeth out of my skull.

 

[Larry]

Larry,

I have an 82 K10 and I'm having a ton of trouble surviving long trips because of the incredibly rough ride. I'll be getting some premium seating, but I'm not sure what to do with my suspension. I'm currently running a 6in Rough Country lift. I saw your suspension setup. Do you have recommendation that doesn't perhaps require and entirely new lift kit? Also, how does your setup feel on corrugated/washboard roads? In my truck, I feel like I'm going to rattle my teeth out of my skull.

Yeah, they don't call those “Rough Country” springs for nothing. I've found the Superlift Softride springs with ORD HD shackles and ORD sway bar disconnect make a big difference in ride even with less than sterling shocks like the Superlift shocks I have (need a shock upgrade on my rigs bigtime). A lot of other people are big fans of BDS springs but I've never had the opportunity to try a set of those. Sounds odd but the ORD sway bar disconnect makes a noticeable difference itself, not because it disconnects but because it corrects the working angle of the sway bar on a lifted truck where the sway bar no longer works like a steel rod jammed between the frame and axle. You'll have to look over ORD's website to read upon them. On the rear, I also run the ORD shackle flips. I swear that helps with ride quality too. Both the lifted K10 and Suburban ride considerably better than my stock 2001 Silverado HD by a long shot. Torsion bar IFS GM HD trucks drive nice but ride horrible….a total explosion of discomfort with every crack in the road. My old K10 and Burb are not that way at all.

Hehe, corrugated roads/washboards are one of my big pet peeves. Most people drive way to friggen fast on washboards (1leglance!!!). The only thing that I find that really helps is running big tires, lowering the air pressure and slowing DOWN! People that have traveled with me on off-road trips get annoyed by me because I drive so slow on washboards. About 10 years ago I traveled with chassis engineers from work where we were testing UPS trucks East of Denver on some horribly rough wash boarded roads. UPS was having issues with our new delivery vans breaking various underhood brackets, suspension components and even tie rods on these roads. We had these trucks fully instrumented with sensors in about 40 locations throughout the chassis (several points on the frame, engine block, seat pedestal, strg column, dash board, leaf springs, tie rods, axles, body, windshield, and tons of other places). What I learned is the faster you go on washboards may feel better to the seat of your pants (no surprise there) but the Hz frequencies are through the roof into the danger zone of fatiguing and breaking metal. Extremely high Hz frequencies will fatigue metal very quickly causing a lot of things to crack and break. The slower you go the lower the Hz frequencies are the better the truck will live. We actually found the front tie rod assembly had a full 6" deflection (3" each way...up and down) on heavily washboarded road at 45 MPH. 6"!!! In the case of UPS our engineers were able to come up with better engineered components to address the items that were quickly breaking but even at that, they would still break it just took longer cycles to get them to break.

I had to laugh, a few years after the engineering trip my MIL and I ran down to Toroweep (horribly washboarded road) and that in the middle of the road was someone's rear tire carrier that suffered from high Hz frequencies fatigue cracking. Also found a roof rack on the side of the rode on a dirt road in CO due to the same thing. If you read the trip report section of this forum there are always people posting pictures of aftermarket bolt on crap that has cracked and broke off their expo rigs on dirt roads. Hmm, wonder why? Slow the hell down on washboard roads if you don't want your rig to fall apart

 

[toddz69]

Hehe, corrugated roads/washboards are one of my big pet peeves. Most people drive way to friggen fast on washboards (1leglance!!!). The only thing that I find that really helps is running big tires, lowering the air pressure and slowing DOWN! People that have traveled with me on off-road trips get annoyed by me because I drive so slow on washboards. About 10 years ago I traveled with chassis engineers from work where we were testing UPS trucks East of Denver on some horribly rough wash boarded roads. UPS was having issues with our new delivery vans breaking various underhood brackets, suspension components and even tie rods on these roads. We had these trucks fully instrumented with sensors in about 40 locations throughout the chassis (several points on the frame, engine block, seat pedestal, strg column, dash board, leaf springs, tie rods, axles, body, windshield, and tons of other places). What I learned is the faster you go on washboards may feel better to the seat of your pants (no surprise there) but the Hz frequencies are through the roof into the danger zone of fatiguing and breaking metal. Extremely high Hz frequencies will fatigue metal very quickly causing a lot of things to crack and break. The slower you go the lower the Hz frequencies are the better the truck will live. We actually found the front tie rod assembly had a full 6" deflection (3" each way...up and down) on heavily washboarded road at 45 MPH. 6"!!! In the case of UPS our engineers were able to come up with better engineered components to address the items that were quickly breaking but even at that, they would still break it just took longer cycles to get them to break.

I had to laugh, a few years after the engineering trip my MIL and I ran down to Toroweep (horribly washboarded road) and that in the middle of the road was someone's rear tire carrier that suffered from high Hz frequencies fatigue cracking. Also found a roof rack on the side of the rode on a dirt road in CO due to the same thing. If you read the trip report section of this forum there are always people posting pictures of aftermarket bolt on crap that has cracked and broke off their expo rigs on dirt roads. Hmm, wonder why? Slow the hell down on washboard roads if you don't want your rig to fall apart

Interesting data! Since I play a mechanical engineer on TV, I'm always fascinated with vibrational data and the effects of fatigue on various components on our rigs. I may be partially to blame for Lance since we give his truck a workout every year in Mexico chasing our race truck in the NORRA Mexican 1000 :sombrero:. But I'm one of those guys that likes to 'get on top' of the washboards when possible for seat of pants comfort, knowing full well that might contribute to additional breakage. I blame high cycle fatigue for several of my aluminum radiator failures in my Bronco (slight shake in the front end at speed) in years past. It's also an excuse to re-engineer components and accessories as necessary to be stronger for the long haul. 350K miles on the old beast now and she's still holding together.

On our DV trip in '08, our trip leader told us that we'd experience the worst washboard/corrugated roads we've ever been on when we traveled the Saline Valley Road and he wasn't wrong. I've driven bad roads all over the southwestern US and it definitely had the worst washboard surface. Our only casualty was a dented jerry can that fell off the back of my truck (it had been strapped onto the spare tire as a last minute packing compromise).

Time for some shock upgrades, Larry!

Todd Z.

 

[Larry]

Interesting data! Since I play a mechanical engineer on TV, I'm always fascinated with vibrational data and the effects of fatigue on various components on our rigs. I may be partially to blame for Lance since we give his truck a workout every year in Mexico chasing our race truck in the NORRA Mexican 1000 :sombrero:. But I'm one of those guys that likes to 'get on top' of the washboards when possible for seat of pants comfort, knowing full well that might contribute to additional breakage. I blame high cycle fatigue for several of my aluminum radiator failures in my Bronco (slight shake in the front end at speed) in years past. It's also an excuse to re-engineer components and accessories as necessary to be stronger for the long haul. 350K miles on the old beast now and she's still holding together.

In our DV trip in '08, our trip leader told us that we'd experience the worst washboard/corrugated roads we've ever been on when we traveled the Saline Valley Road and he wasn't wrong. I've driven bad roads all over the southwestern US and it definitely had the worse washboard surface. Our only casualty was a dented jerry can that fell off the back of my truck (it had been strapped onto the spare tire as a last minute packing compromise.

Time for some shock upgrades, Larry!

Todd Z.

You're right, we did DV in 2013 and Saline Valley was loaded with washboards. I don't recall any of us breaking anything on that trip either but that was also the trip where my rear axle first started barfing oil.

I do need an upgrade in the shock department for sure. Looking at Bilstein 5100's and reworking all of the shock mounting brackets this winter. The Burb is going to need an upgrade as well as the Superlift shocks aren't cutting it. Something similar to what Lance has on his burb but without the bump stops. Any suggestions on shocks?

 

[toddz69]

I do need an upgrade in the shock department for sure. Looking at Bilstein 5100's and reworking all of the shock mounting brackets this winter. The Burb is going to need an upgrade as well as the Superlift shocks aren't cutting it. Something similar to what Lance has on his burb but without the bump stops. Any suggestions on shocks?

The 5100s wouldn't be a bad starting point although you might end up wanting a little more. About 8 years ago I changed from Bilstein 7100s to 2.0 Foxes on the front end of my Bronco:

http://www.ridefox.com/product.php?m=offroad&t=shocks&p=3384&ref=filter

I ended up with 7/8" shafts but the 5/8" shafts would work fine too. If you'd rather not do spherical rod ends, ORW has urethane bushings for them instead. Good quality and have proven to be very durable.

I still have Bilstein 7100s on the rear end and they're great.

Todd Z.

 

[xripx]

Yeah, they don’t call those “Rough Country” springs for nothing. I’ve found the Superlift Softride springs with ORD HD shackles and ORD sway bar disconnect make a big difference in ride even with less than sterling shocks like the Superlift shocks I have (need a shock upgrade on my rigs bigtime). A lot of other people are big fans of BDS springs but I’ve never had the opportunity to try a set of those. Sounds odd but the ORD sway bar disconnect makes a noticeable difference itself, not because it disconnects but because it corrects the working angle of the sway bar on a lifted truck where the sway bar no longer works like a steel rod jammed between the frame and axle. You’ll have to look over ORD’s website to read upon them. On the rear, I also run the ORD shackle flips. I swear that helps with ride quality too. Both the lifted K10 and Suburban ride considerably better than my stock 2001 Silverado HD by a long shot. Torsion bar IFS GM HD trucks drive nice but ride horrible….a total explosion of discomfort with every crack in the road. My old K10 and Burb are not that way at all.

Hehe, corrugated roads/washboards are one of my big pet peeves. Most people drive way to friggen fast on washboards (1leglance!!!). The only thing that I find that really helps is running big tires, lowering the air pressure and slowing DOWN! People that have traveled with me on off-road trips get annoyed by me because I drive so slow on washboards. About 10 years ago I traveled with chassis engineers from work where we were testing UPS trucks East of Denver on some horribly rough wash boarded roads. UPS was having issues with our new delivery vans breaking various underhood brackets, suspension components and even tie rods on these roads. We had these trucks fully instrumented with sensors in about 40 locations throughout the chassis (several points on the frame, engine block, seat pedestal, strg column, dash board, leaf springs, tie rods, axles, body, windshield, and tons of other places). What I learned is the faster you go on washboards may feel better to the seat of your pants (no surprise there) but the Hz frequencies are through the roof into the danger zone of fatiguing and breaking metal. Extremely high Hz frequencies will fatigue metal very quickly causing a lot of things to crack and break. The slower you go the lower the Hz frequencies are the better the truck will live. We actually found the front tie rod assembly had a full 6" deflection (3" each way...up and down) on heavily washboarded road at 45 MPH. 6"!!! In the case of UPS our engineers were able to come up with better engineered components to address the items that were quickly breaking but even at that, they would still break it just took longer cycles to get them to break.

I had to laugh, a few years after the engineering trip my MIL and I ran down to Toroweep (horribly washboarded road) and that in the middle of the road was someone’s rear tire carrier that suffered from high Hz frequencies fatigue cracking. Also found a roof rack on the side of the rode on a dirt road in CO due to the same thing. If you read the trip report section of this forum there are always people posting pictures of aftermarket bolt on crap that has cracked and broke off their expo rigs on dirt roads. Hmm, wonder why? Slow the hell down on washboard roads if you don't want your rig to fall apart

When you say "Softride" springs, do you mean "Superide?" I was looking on Superlift's site and I only see Superide referenced, where Skyjacker has Softride. My truck also has no sway bar to speak of and I have zero body roll.

Currently, the way my rig is setup, would I be able to get close to your ride quality if I get 6" Superlift Superide springs and ORD HD shackles in the front, shackle flip kit and 2.5" Superide springs in the rear?

 

[Larry]

The 5100s wouldn't be a bad starting point although you might end up wanting a little more. About 8 years ago I changed from Bilstein 7100s to 2.0 Foxes on the front end of my Bronco:

http://www.ridefox.com/product.php?m=offroad&t=shocks&p=3384&ref=filter

I ended up with 7/8" shafts but the 5/8" shafts would work fine too. If you'd rather not do spherical rod ends, ORW has urethane bushings for them instead. Good quality and have proven to be very durable.

I still have Bilstein 7100s on the rear end and they're great.

Todd Z.

Good info! I may be shaking your tree before I make my shock purchase. Thanks Todd!

When you say "Softride" springs, do you mean "Superide?" I was looking on Superlift's site and I only see Superide referenced, where Skyjacker has Softride. My truck also has no sway bar to speak of and I have zero body roll.

Currently, the way my rig is setup, would I be able to get close to your ride quality if I get 6" Superlift Superide springs and ORD HD shackles in the front, shackle flip kit and 2.5" Superide springs in the rear?

Yep, you’re absolutely correct…they’re called Superide. Dunno why I keep calling them Softrides. LOL

Well, I don’t know for sure you will get the exact ride as mine as my two rigs are pretty heavy with big blocks, etc. over an light unladen pickup and I am only running 4” lifts instead of 6” but it is pretty safe to say a better spring will yield a better ride. BTW, I doubt Superlift are the best, it’s just what I’ve used and it works for me. The best would probably be BDS or Alcan’s. The price isn’t bad for the 01-234-6 Superlift 4” springs though….$80 each per spring through Summit Racing.

FWIW, the Superlift Superide 01-234-6 (don't confuse the 6 in the part number as 6"....that pn is a 4") springs on my K10 are about 10 years old and were made in India while my Suburban springs are a little over a year old and made in the USA. The two same part number springs of different ages and manufacturing locations look a bit different in the leaf thickness and locations of the rebound clips but they both ride well for SFA trucks. The K10 naturally rides nicer because it is so much heavier. Back before this truck gained ORD goodies, Superide springs and A LOT of weight it rode like a mule too.

 

[1leglance]

My butt comfort is more important that parts breakage....especially when I am giggling like a little girl going fast on washboard.
I remember you telling me the data thing a few times Larry, oh well I am still going to go fast on the washboard

I have found that my custom leaf springs, Fox reservoir shocks and front hydraulic bump stops and airing down make it way more fun to go quick in the desert, so I do and I accept the increase in likely failure. However that doesn't mean other folks should beat up their rigs....

And Larry you drive slow everywhere
And I am still happy to be on the trail with you Colorado characters!