So ive had a bad week with gearcases
My fault, should have known better, I do know better.
I was having fun doing burnouts. Blew apart shattered my 3rd member. Some wheel hop caught me off guard, maybe hit a pothole not sure exactly it was dark and I didnt stop. Drove home slowly about half mile.

Broke both caps, trashed the ring and pinion. Left a nice dent in the housing where the trac lock and ring gear tried to escape. The axles actually held the differential (ford trac loc) in place enough to keep it in contact with the pinion and get me home.

So I'm looking at a complete rebuild now with a new case, or buy one already assembled and this brings me to some questions for you guys

1. Has anyone used the eaton/detroit true trac (gear driven LSD) and advantages vs clutch type posi. (There is a number of mfgs for both types so any advise with either type is helpful)
I do not want a locker being 99.9% on road driving.
I ask because ive already rebuilt the clutch pack. Most times still get only one tire to break loose. (Burnouts aside I'm done with that) at boat ramp most times I have no issue crawling up out of ramp but if one tire slips and begins to spin forward momentum will stop. I'll have to back off brake stop all tire spinning and attempt it again. I would expect it to transfer power to other side.
do the gear drives work that much better?

Even though I did not hurt my clutchpack tracloc the inner splines are beat up pretty good as is the axle splines. So while doing this I might as well do all for the last time. I'm not putting beat up axles in a new unit. Nor will I put new axles in a beat up unit. I plan to change the oil in this diff when I'm done and thats all I ever want to do again with it.

which leads to the next few questions.

2. If doing it all is it worth the extra $100-150 to go to 35 spline axles?

3. If I'm buying a empty case the cost is minimal to go to the larger carrier bearings. (If I go 35 spline I believe it has to be the larger bearings) the question here is if I stick with 31 spline does it really make a big difference.

4. Edit upon more research no alum 3rd members

I'm open to suggestions. Building myself or buying a.complete 3rd member. Building myself saves a good chuck of cash but maybe id get lucky and find one at a good price already together.

I went to local junkyard and I'll just say that place was *methed* up bad. All his good stuff (been in yard for 20+ yrs) laying in dirt he would not separate would only sell the complete axle for $800
one axle still under a truck missing pinion support and dirt up to the flange. Prob full of dirt said would lift with fork lift and I remove it for $300 bucks just the center..id be doing that just for the case. I can buy a brand new one for less than $300

heres some pictures (also yesterday while running thru some skinny water to a fishing hole on my boat I located a rock just under the surface of the water doing a bang up job on my lower unit) that is the other part of the bad gearcase week.




Witness marks where the ring gear tried to escape the carnage

What a mess

Least my gear mesh looked good (it was my first time)

What remains of the caps




This really hurt gona be about 3 times cost of the 9\" repair Cracked shaft bearing housing bent shaft

Misisng large piece of skeg

Mangled prop



I'

 

I have an Eaton Trutrac in my 9". It's a 31 spline, 3.5:1. I'll never go back to a clutch type, or a Detroit Locker type differential. The Trutrac is seamless. You won't even know it's back there, until you need traction.

 

Other than that, how was the fishing ?

 

35 spline axles would not have helped here....the third member casting gave up...the axles were just place holders.

I would get a complete donor axle, swap breaks and other good parts you can to the donor...add a true-trac and install in your truck.

Will be cheapest solution with very good results IMO.

Nice job!

sorry to see the outboard damage...

I am very unimpressed with my brand-new Dana Corp clutched diff in my D60....I really need to put a tru-trac or similar geared unit in it and be done with it.

 

No you're not!

 

Ranger, thanks that is what i thought and most likely the route I will be going.

Mark, it was not terrible in hour caught 1 red fish dozen mangrove snapper and dozen lady fish. Once we left that spot and realized it was more than a bent prop. Stopped at two more spots on the way back limping her along. At the second stop the livewell pump stopped working, I was fed up and not in much of a mood to teach two guys new to fishing how to fish with artificial bait. We headed back in. Neither stop 2 or 3 produced anything.

 

Man that day totally sucked.

 

I’d vote no on the 35 spline stuff too. That’s high HP big tire stuff. 31 spline will be just fine.

The geared style limited slip diffs are very good. If you got the $ for one you won’t be upset with it.

Again I’d vote for getting a complete used 9” and upgrading that to your needs. And bad as your axle was trashed it’s possible your housing is bent and it’s not worth that chance.

 

At.least on dry pavement, I dont want to do it again.

I never even considered the housing bent. I'll have to check that. Really long straightedge thru the center one side to another and get out the ruler.

When I went to the local junkyard that wanted $800 for a complete axle, then it needing a complete rebuild and posi unit, all bearings etc. I can get bare 3rd member 400 or less ans still need to purchase everything on the rebuild to build the new unit. Bearings posi unit etc. I dont see any way its any cheaper going used.

Now if my housing is bent I'll need the used unit to do a.complete rebuild on. I'll figure that out in next day or two. I'll have to pickup something to use to measure.

Is 800 for a core 9" axle needing complete rebuild the going rate these days and I'm stuck in the 90s or was that place just crazy?

 

And, if I learned anything from Gale Banks's research, that witness mark/distortion in the rear of the housing might be enough to disturb the 'flow' of the oil being carried up the rear of the ring gear - if I remember that right.

 

Pic from the inside where ring gear and tracloc hit

 

Around here..new england..you can find complete $3-400 9" axles on Facebook or Craigslist. I've sold 2 in the last couple years in that range. Worst case you might need to get something from another model and move the spring perches.

 

Banks is a showman, but it's hard to discredit his video about aftermarket diff covers. After watching that video, I'd be a little concerned about that big gouge. Not only for fluid dynamics, but for structural integrity as well.

 

Need advise ? -

My advice is : 1 - Not to rag on any vehicle with factory installed parts that are not made for extreme abuse...

and 2 - Upgrade to a more durable diff unit like others noted if one desires to continue to abuse their vehicles while having fun and having piece of mind with durability.

 

Back together and running/driving. Got 300-500 mile break in to go before towing.

Checked housing as best I could to determine it was straight, repaired the gouge by welding and grinding. Both in and outside. It was so thin a few places the tiny tack welds were coming thru the outside. I watched a few of banks videos and yes he sure is a showman but make solid points. So the inside I repaired as much as I could to be as if it wasn't there. Was alot of welding and grinding.

While it was out I noticed the spring block mounting locations were bent a little. Little heat with torch and a stout flat punch to straighten them out. Then cut and welded a gusset into all 4 openings.

For a 3rd member I went with currie enterprises twintrac helical gear LSD completely assembled.

Couple brand new axles, bearings, retainers. Painted everything back up and threw it together.

While down pulled trans and transfer case to swap out the flywheel ring gear.... That was fun! My.buddy called it a magic trick.

Pics to come I have to swap to a different platform.