need info ASAP - detroit locker

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Fantom said:
I do agree with you Dan. City driving is tough on fully time locked differentials, axles and tires. This is where full time locked differentials suck, and I will never do that again. Even in off road application there are many times I would have had an easier time with the locker turned off. It's impossible to prove what killed it in the end, in off-road use you get random, more instant shock from obstacles and on average we drive the vehicles harder than we do in the city. In city use you get no give from mud and soft dirt, and the stress is almost sustained for the duration of driving. Flip a coin.

ForealBoreal, .....it will be done .....eventually :D and have to find the engine before I do anything else. Toyota, used, diesel drivetrain is over priced. Last time I found a guy selling a 13BT, 5 speed, transfer that was 20 years old, withunder 200,000kms, for $8,000. I'm sorry, I'm not about to pay that much money for an setup that has no history, for all I know it was treated like crap its entire life and I'll get 50,000kms out of it. The used market value for these engines has been hiked up way too much. I can get an entire truck, with a Cummins diesel with under 300,000kms for $3-5,000 - that's an entire truck. I get my engine, wiring, and whatever else, sell the body, frame and axles and I'm done. I am seriously looking at going that direction now. We'll see what happens.
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There is a BJ73 for sale $6000 asking , body rough 121,000 km on engine!. Get compression checked. Steve has 13BT exhaust manifolds - turbo it (intercool?) and you have engine, transmission and T-case, you have the OEM locker diffs. I may go in for some parts if you want.
1985 Toyota Land Cruiser BJ73 - Vancouver Cars For Sale - Kijiji Vancouver Canada.
 
Keep in mind that the BJ73 has a rotary pump. I don't know if you care about that or not.
Could be a good little buy as you could sell some of the things off of it if you willing to do the work and have the space.

The other idea is you can pick up a 3b for next to nothing. Just a thought.
 
Got the locker ripped apart, bought a new 8mm 1.25 bottom tap (nice and short point for blind holes), marked everything out and after some head scratching I finally secured the stupid thing in the drill press and went to town.
Go 6 brand new holes drilled, 8.5mm in the cover to give 0.5mm clearance around the bolt, and a hole right into the housing.
Spaced them out in the middle of the old holes, with the exception of the 2 around the pillow block, which were further apart due to the size of the pillow block hole.
It was easier to align everything with the cover bolted to the housing with the 2 existing bolt holes that were not destroyed.

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Now for the pillow block solution....hmmm....
That is the only bolt that survived, but it has been knocked around and there looks to be some discoloration of steel. So it is not safe to reuse - might get a couple kilometers out of it and loose the pillow block - ouch!
So, now what.....it is a specialty sized bolt that no one carries, Detroit (Eaton) is still ignoring my e-mails - they can officially bite me now.
All the off the shelf bolts that are long enough do not have thread that goes far enough on the bolt, so I have to add more thread to the bolts by using a die.
I'm hoping to have it back together tomorrow.

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Are you going to use the old bolt holes as well doubling the bolts holding it together? Interesting to see this as Gavin has the same locker in the back of his HJ.

Edit: I just re read a few posts back and saw the plan, interesting how they seemed to have stretched beyond the yelled point. I would have thought that most the force would have been supported by the carrier bearing pre load, using the bolts to really only keep the two halves from spinning separably.
 
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Thanks Dan.

Jeremy, you are partially correct, yes the bearings and the preload do keep the locker together, which is the only reason why mine held still. The bolts do keep the housings from rotating, but more importantly they keep the housing together and take the additional stress of the springs off the bearings. If the bolts were not there, that would significantly increase the preload on the bearings and cause them to wear and fail at an alarming rate.
Why they failed.....I can only guess 2 reasons:
1 - the quality of bolts was sub standard
2 - they were over torqued during installation (who ever put the locker together - if it was Eaton or IWE, I will never know) - I'm leaning towards this one personally. The housing cover has fairly deep gouges from the bolt heads being torqued down.

Now back to the rebuild:
Got the bolt thread extended with a die (grade 8 bolts suck for cutting new threads into), swore at the locker as I tried putting it back together and came to the conclusion that trying to align 6 gear spots at once, while fighting with 2 powerful springs was not a good idea. So I did it step by step.
This time we have red lock-tite on the new M8 bolts, all torqued to the BOLT's specified torque of 29ft/lbs, while the springs are compressed by the threaded rod in the middle (taking the extra pressure off the cover and giving a false torque spec).

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That white grease is engine assembly, generic, white lithium grease.

Got everything installed, place all the bearings and nuts to where they were before disassembly (I marked everything). Checked the backlash and found that it was at 0.33mm. The factory manual calls for 0.15-0.20mm, so over the last 100,000km (if they were set up right) the backlash has pretty much doubled. Had to make myself a custom SST, flat bar and a couple bolts later.
After a little playing around I got it to 0.18mm all around and got good wear on the teeth as well. Good enough for me, in she goes!

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Got everything buttoned up and torqued, lubed, sealed, reinstalled, hit with a hammer for good luck and it started pissing rain so I put off the mounting of the tires and the test drive for tomorrow. All felt good and rotated smoothly, we'll see how well it does at 100km/hr

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Yes - but its still a Detroit -

kidding aside - great workmanship Matt -
many happy trails :beer:
 
yea, yea, I know. But more importantly, the truck drives and I'm not out $500 for another one. Thanks Glenn.
Did a short test drive, no noises, seems to be working well. More detailed test tomorrow and I need to get the front aligned, but the truck once again, in good mechanical condition.
 
My guess they were over torqued when installed and from the instructions I posted they come in a bag with locktite already on - so the implication is the "installer" over torqued them -- they busted mid length and the locktite was unable to keep them in and and they worked their way - given the the way the Detroit works (bang) they would come out fairly fast.
my $0.02 worth.
 
Good job Mat.

Glenn, if I remember correctly, the locker comes pre-assembled, probably so it fits in a smaller box. Only the one bolt on the pillow block comes partially installed.

Seems all (almost all?) the locker options out there have their weaknesses :meh:
 
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