Tractor vs Cruiser...yeah...the tractor won...

[lostih]

I wasn't even being rough with it, but I guess it was a bone head thing to do. Backed my tractor into some fill dirt that was too soft and it got a little tipsie so I decided to chain the cruiser to it and give it a yank. Well...I think that cost me my front diff :-( The tires were spinning ever so slightly but I was on wet grass and didn't think it'd be enough to munch the diff, but the horrible clunk in the front about every 4 feet seems to say otherwise. So here's the question...the barn where I'll have to take this apart to see what's wrong with it is about 300 feet away...do you think I need to pull the front driveline and driveplates or would you drive it the 300 ft? I've probably driven it 50 feet before I was convinced that something is definitely not right up front.

 

[e9999]

well, you are going to take the front bits off anyway, so if it's as easy as flanges and a driveshaft to get it to the barn safely, why not remove those out there? I would not drive it like that 300ft. A rotation or 2 with floating metal could make a difference in the state of affairs in there.

 

[lostih]

Good point! I hate opening it up on the gravel but I suppose its just the drive plates.

Anyone upgrade to an ARB and have an extra 4 spider gear carrier they want to part with?

 

[sdnative]

Not sure if this helps.

Genuine Factory OEM Lexus LX470 '98 -'03 Front Differenital Carrier

Genuine Factory OEM Lexus LX470 '98 -'03 Rear Differenital Carrier

 

[lostih]

Not sure if this helps.

Genuine Factory OEM Lexus LX470 '98 -'03 Front Differenital Carrier

Genuine Factory OEM Lexus LX470 '98 -'03 Rear Differenital Carrier

Thank you! Sent him an email. I'd love to find a 4 side gear version so this doesn't happen again...but heck...If I get out of this for bearings and a $50 carrier I'll be thrilled!

 

[e9999]

Good point! I hate opening it up on the gravel but I suppose its just the drive plates.

snip

if you remove the hub driveplates, the wheels won't make the diff turn, which is good. However, I imagine the full-time 4WD will keep the front driveshaft spinning with the engine which will rotate things inside too, and that would not be good. So, unless you put the TC in neutral and push/pull the truck, I'd disconnect the front driveshaft too. If you do that you could have the engine and rear wheels do the job but you'll need to lock the center diff.
Or use a dolly with big enough tires for the gravel.

 

[lostih]

Well I pulled the driveshaft and drive plates and drove to the barn. Pulled the front cover off...and ta-da! Sheared a bunch of teeth of the ring gear. Can't see the pinion but found one of its teeth in the oil.

Is this common? I thought it was the spider gears that went in early diffs...

 

[e9999]

did you pull in reverse?

 

[lostih]

Nope. Pulled forward on mostly level ground starting from rest.

 

[staggrlee]

"so I decided to chain the cruiser to it and give it a yank"...

Hardly productive at this point, but you need to be a little more deliberate in performing a stuck assessment. A chain is not snatch strap and the shock load to the vehicle drivetrain on take up doesn't care how gentle you think you're being. There was only one likely outcome (especially with a two pinion diff) and you're very lucky that only vehicle damage was the result.

 

[montegofd3s]

^ I am sure he will be more careful next time.

 

[SALTY METHODS]

Question... Can you do straight across replacement of a `98-`99 2-pinion front differential with a later model 4-pin differential? Is that a cost effective way of getting more durability without having to buy a new ARB front diff? I was thinking of keeping my eye out for a later model junk yard diff. if that is possible.

 

[yotasavg]

"so I decided to chain the cruiser to it and give it a yank"...

Hardly productive at this point, but you need to be a little more deliberate in performing a stuck assessment. A chain is not snatch strap and the shock load to the vehicle drivetrain on take up doesn't care how gentle you think you're being. There was only one likely outcome (especially with a two pinion diff) and you're very lucky that only vehicle damage was the result.

I don't have much experience tugging things, but I'd like to understand this more. Can you please elaborate?

 

[staggrlee]

I don't have much experience tugging things, but I'd like to understand this more. Can you please elaborate?

When recovering a stuck vehicle the largest load occurs breaking the inertia/getting the thing moving initially. You don't use a rope/chain/cable for this but instead a "kinetic recovery" or snatch strap/rope. As you take up the load, the strap stretches and provides some of the umph to break the static friction and simultaneously reduces the shock or instantaneous load on the recovery vehicle/drivetrain.

 

[lostih]

Question... Can you do straight across replacement of a `98-`99 2-pinion front differential with a later model 4-pin differential? Is that a cost effective way of getting more durability without having to buy a new ARB front diff? I was thinking of keeping my eye out for a later model junk yard diff. if that is possible.

I believe that is correct from my research though I've never done it. However, I've hit up the local yards and nothing pops for ANY front diff for these guys...

 

[lostih]

When recovering a stuck vehicle the largest load occurs breaking the inertia/getting the thing moving initially. You don't use a rope/chain/cable for this but instead a "kinetic recovery" or snatch strap/rope. As you take up the load, the strap stretches and provides some of the umph to break the static friction and simultaneously reduces the shock or instantaneous load on the recovery vehicle/drivetrain.

Ok now I understand where you are coming from. In my application I took the slack out of the chain and pulled so the shock load was pretty negligible. Also, I don't think it was that sort of shock load that typically breaks a ring and pinion...my working theory is that the tire somehow suddenly got traction on wet grass...not sure how that happens...but it must have. Again, happy I broke it in the driveway, but wish there was a better story...like climbing a knarly wall or something where you knew you might break it.

Good news is I'm leaning towards regearing since I'm buying new gears anyways and the stock ration is $100 bucks more than 4.88's.

 

[yotasavg]

When recovering a stuck vehicle the largest load occurs breaking the inertia/getting the thing moving initially. You don't use a rope/chain/cable for this but instead a "kinetic recovery" or snatch strap/rope. As you take up the load, the strap stretches and provides some of the umph to break the static friction and simultaneously reduces the shock or instantaneous load on the recovery vehicle/drivetrain.

Nice, thank you. That makes good sense.

 

[staggrlee]

That tire bounce is exactly the kind of shock load I'm talking about. One moment, no load. The next, all of it. A kinetic strap effectively stores the energy of the shock load(s) and releases it in a good steady pull on the stuck vehicle that your truck on its own isn't capable of.

All that aside, you've got some good resources here in the PNW for gears/lockers etc. No point dwelling on it. Live and learn. "That which doesn't break me, makes me stronger. That which I break, I make stronger."

 

[Muddy Bean]

staggerlee, you have good intentions, so take this with a grain of salt, I grenaded my front diff in a driveway with snow. No towing, no tugging, no bouncing/hopping or antics. It happens. Good for you for actually using your truck. The front diffs on these are a known weakness. I have beat my other trucks far worse and never suffered a diff failure. It's good it happened at home, and this is precisely why I upgraded to an ARB locker up front. I would recommend this if you continue to actually use your truck as a tool Which I completely endorse.