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Just wondering if any has any experience with a bad detroit?

I have a Dana 70 axle in a 78 Bronco with a 460, C6 auto trans, 4.56 gears, and 38.5" boggers. That axle should be more than enough. I have had a detroit locker in it for maybe 2 years. I don't take it out often, but when I do I push it hard. Anyway I was doing some inspections and noticed the rear driveshaft has about 1/3 turn of play. That play is not the gears, but in the locker. Also I used to be able to turn either tire forward and back a few times and then it would unlock and spin freely in reverse, but not now.

All that adds up to a broken locker to me. So what's wrong with it? Can I have it rebuilt or just replaced? Warranty is 100,000 miles in a new vehicle, but only 1 year in used vehicle.
 

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All Detroits have a ton of play in em, its how they work.

As for unlocking, pull the cover and take a look. Probably need to change your fluid anyway right? Bettin its just gunked up from not being run very often.
 

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I dont think the drive line spin is abnormal when I used to drive mine on the steet it was always a trip to put it in park lift your foot of the brake and roll six iches or so before every thing would lock up they all seem to have a ton of play..
As far as the locker un locking or racheting mine is sometime hard to get it to let go and you have to spin the tire hard by hand does it seem fine when wheeling ?
Mine has proven very reliable 14 years now I think
 

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my detroit manual says "the total driveline slack can amount to as much as 1/4 turn of the driveline without being abnormal"

test the detroit:

1. engine of. jacked up, both tires off ground.

2. rotate both wheels rearward as far as possible to lock both wheels.

3. with left wheel held securly in the rearward direction, rotate the right wheel slowly forward. a faint indexing or clicking sound should be heard as the detroit disengages on the right side.

4. with the right wheel slowly rotating forward, the left wheel should be rotated slightly foreward. this will lock both wheels.

5. again, rotate both wheels rearward as far as possible to lock both wheels.

6. hold right wheel in the rearward direction, rotate the left wheel in the forward direction to hear the clicking.

repeat to test for reverse engagement.
 

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Funny this thread is up now.. After 9 season on my toy 8" :D it started acting funny 2 weeks ago on fordyce. I would get about the 1/4 of driveline then a good click/pop. Just now drained the fluid (camo brown green). Can the fluid loosing its lubrication properties cause some of this? Gears are tight, backlash is still good..... Guess I will just clean it out, fill it up with fresh oil and run it until it breaks!!
Ideas?
 

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nc

i think i see u on nc ... there is a thread there i think 3 were broke at dixie run or harlan
 

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Imuz- If I were you I'd go ahead and take the detroit out and tear it down. Sounds like it's getting ready to shit the bed on your next trail ride. They're pretty simple inside. Just make sure you've got an extra set of hands or put it in a vice when you take the bolts out. It has 2 large springs that will throw parts just far enough for you not to find one of them. I've seen more than 1 welded up detroit due to the noises your are starting to hear.
 

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i think i see u on nc ... there is a thread there i think 3 were broke at dixie run or harlan
That was Harlan. It seems mine has been broken for awhile now. I thought it was the hydraulic steering acting funny all this time. Both sides of mine still pull, its just steers worse than a welded front. At Harlan it got to where I couldnt steer at all. I had to front dig to get it to turn. Two other rigs in my group took out their detroit too. One is doing the same as mine and the other just quit pulling on one side I believe.

Any doubt, tear it apart at home. If I had known what was wrong the first time I think I could have fixed it for about 200$. Now its gonna have to have a new detroit.
 

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Just wondering if any has any experience with a bad detroit?

I have a Dana 70 axle in a 78 Bronco with a 460, C6 auto trans, 4.56 gears, and 38.5" boggers. That axle should be more than enough. I have had a detroit locker in it for maybe 2 years. I don't take it out often, but when I do I push it hard. Anyway I was doing some inspections and noticed the rear driveshaft has about 1/3 turn of play. That play is not the gears, but in the locker. Also I used to be able to turn either tire forward and back a few times and then it would unlock and spin freely in reverse, but not now.

All that adds up to a broken locker to me. So what's wrong with it? Can I have it rebuilt or just replaced? Warranty is 100,000 miles in a new vehicle, but only 1 year in used vehicle.
Bad detroits seem to be very common these days even on mildly powered moderately wheeled rigs on smallish tires. I managed to screw both front and rear D60 detroits in 2 years on a 2.3 litre LandRover on 36'' tyres,enough so that positive drive to all wheels on steep rocky climbs was never assured. I threw them out and fitted homebuilt manual locks after a few scary incidents on long steep offcamber descents that my companions with manual locks had no problem with. Yes I am a crap driver, but after fitting manual locks the same descents and ascents were a breeze in all weather conditions.
As a medium and heavy truck driveline mechanic I have replaced a lot of broken low mileage Detroits on these rigs, so IMO there is certainly a material/design quality issue that has manifested itself in the past 15 to 20 years or so. A friend of mine has a 30 year old 9'' Ford Detroit in a heavy high powered LandRover that has survived countless broken 31 spline axles and a grenaded housing including peeling off 20 ring gear teeth without any damage to the locker or carrier itself.The design difference is that his doesn't have the annular grooves machined into the side gears for the so called holdout rings.These groove substantially reduce the cross sectional area of the dog teeth and for some reason concentrate the shock loads on the inner circle of dog teeth when an axle shaft lets go. The material difference between his and mine is that all the side gears, drivers, cams etc are cut ,milled and splined from forged steel blanks whereas my later so called ''S'' (for silent)series have been either investment cast or pressure moulded from sintered metal.
Bill.
 

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Imuz- If I were you I'd go ahead and take the detroit out and tear it down. Sounds like it's getting ready to shit the bed on your next trail ride. They're pretty simple inside. Just make sure you've got an extra set of hands or put it in a vice when you take the bolts out. It has 2 large springs that will throw parts just far enough for you not to find one of them. I've seen more than 1 welded up detroit due to the noises your are starting to hear.
Well I already pulled it, cleaned out the entire 3rd and locker, put the rear end back together, I'm going to run it and see what happens. Supposed to hit Fordyce in 2 weeks. Keep you guys posted. If it blows, it's getting a spool, I will fix the detroit and sell it! I have never heard of these things blowing up. Wierd!
 

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Bad detroits seem to be very common these days
As a medium and heavy truck driveline mechanic I have replaced a lot of broken low mileage Detroits on these rigs, so IMO there is certainly a material/design quality issue that has manifested itself in the past 15 to 20 years or so. The design difference is that his doesn't have the annular grooves machined into the side gears for the so called holdout rings.These groove substantially reduce the cross sectional area of the dog teeth and for some reason concentrate the shock loads on the inner circle of dog teeth when an axle shaft lets go. The material difference between his and mine is that all the side gears, drivers, cams etc are cut ,milled and splined from forged steel blanks whereas my later so called ''S'' (for silent)series have been either investment cast or pressure moulded from sintered metal.
Bill.
Reading this really makes feel good about the new Detroit I just installed in my Ford 9.75":shaking::mad3: It was the only full locker offered for that axle so I didn't have much choice. I also went by the past experience I had with the front and rear detroits in my Toy p/u. Those have been used and abused since about 1990 or so, and are still going strong.
 

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I just blew up a 2 year old detroit (D44) with a 3.0L nissan engine, (that has 345K on it).

Never again, will i buy a detroit. I was crawling up a small ledge that i've been up a dozen times or more.

tires were not spinning, no bouncing,,, just BANG.

Legendary durability.. ya, its a legend, everybody talks about it, but never seen it.:mad3:
 

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Hmm...

Mine work great. Be the crap out of them frequently and nary an issue. The one in the rear came from a '80s CUCV 1-ton truck so it's well used.
 

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Bad detroits seem to be very common these days even on mildly powered moderately wheeled rigs on smallish tires. I managed to screw both front and rear D60 detroits in 2 years on a 2.3 litre LandRover on 36'' tyres,enough so that positive drive to all wheels on steep rocky climbs was never assured. I threw them out and fitted homebuilt manual locks after a few scary incidents on long steep offcamber descents that my companions with manual locks had no problem with. Yes I am a crap driver, but after fitting manual locks the same descents and ascents were a breeze in all weather conditions.
As a medium and heavy truck driveline mechanic I have replaced a lot of broken low mileage Detroits on these rigs, so IMO there is certainly a material/design quality issue that has manifested itself in the past 15 to 20 years or so. A friend of mine has a 30 year old 9'' Ford Detroit in a heavy high powered LandRover that has survived countless broken 31 spline axles and a grenaded housing including peeling off 20 ring gear teeth without any damage to the locker or carrier itself.The design difference is that his doesn't have the annular grooves machined into the side gears for the so called holdout rings.These groove substantially reduce the cross sectional area of the dog teeth and for some reason concentrate the shock loads on the inner circle of dog teeth when an axle shaft lets go. The material difference between his and mine is that all the side gears, drivers, cams etc are cut ,milled and splined from forged steel blanks whereas my later so called ''S'' (for silent)series have been either investment cast or pressure moulded from sintered metal.
Bill.
I bought a Detroit off of ebay to replace the one I broke at TTC07- this was an older unused one that I hoped would be stronger than the current design- looked exactly the same. the date on the tag was 1980, so if older ones are are stronger, I guess you need to go older than that. I got this one cryoed- doing OK so far.
 

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its pretty damn hard to break that locker. Unless you shitcanned your gears or your shafts, your locker is probably fine. Maybe it just needs a little re-adjusting and new oil.
 
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