Thread: Detroit Locker slipping occasionally....

Mine used to bang and crash a bit during tight manouvres on road, but since I had my centre diff reshimmed, it has disappeared completely.

Mine is a bit jerky at slow speed but, similar to Ron , has settled down a lot as it wears in. No bangs yet.....thanks for the warning!

I find that mine does it after it has sat for a while and you turn a 90 degree corner.
As I accelerate away on rare occasions it will release.
It has probably only happened once or twice in the last 12 Months.
For all those who say it doesn't happen to them don't be surprised when it does I thought I had broken an axle when mine first did it.
Its also possible that if the axle housing isn't straight this behavior could be more prevalent

Originally Posted by 101 Ron

My detroit does nothing in the way of noise or jerks, on road or off.
Only some times on full lock on a hard surface I can feel a slight change speed of the vehicle..........like backing back on full lock when the detroit unlocks and starts driving on the inside wheel.

Hi Ron,
Any ideas why mine might be doing the jerking thing at low speed, low revs wile turning?

Mine did it till I had my centre diff reshimmed, hasn't done it since. Could be coincidental...

Hi Kelvin. It has happened when I've been under acceleration in a straight line in 2nd or 3rd gear, having just pulled out of a junction. Touch wood it has not done it since.. Re being jerky... Yes, same here, especially on a roundabout when you take your foot off the throttle. Drive on the inside wheel (when turning to the right) is then transferred to overrun in the left wheel as you decelerate causing the jerk. The new Isuzu 34 CFS appliances are really bad for this too. I find I make sure I slow down before turning then accelerate through the corner to eliminate the jerk. Correct way to approach a corner anyhow!!

Originally Posted by Ranga

Hi Ron,
Any ideas why mine might be doing the jerking thing at low speed, low revs wile turning?

You must understand how a Detroit works a little bit.
If you are on full lock after going in a straight line the outside wheel must unlock.
This happens because there are no differential.......or equalising gears in the diff centre with the detroit.
When the detroit unlocks on a tight turn the inside wheel is now driving while the outside one is unlocked.
Because the inside wheel has less distance to travel in a arc to go around the corner and it is driving it has the effect of driving the vehicle a little bit faster and at low speeds and full lock it is possible to feel this as a jerk or if the vehicle just increasing speed just for a very short time.
When the vehicle has finished doing the tight turn it will just lock up again and all the wheels will be going the same speed again and driving though all wheels.
When travelling at high speeds and on less tight turns it is usually imposible to feel the detroit working on a constant 4Wd system.
I would if you feel there is a problem , just jack the vehicle up and check if the centre diff lock is unlocking, as if is not it would greatly magnifiy the on road effects of a detroit.( and alot of other things)
Some stated in a earlier post, diff set up could be a factor on how well the detroit behaves on road.
In my my 101 with a salisbury just like a defender 130 I use 80/90 gear oil and when my detroit was fitted the crown / pinion teeth were bearing blued
to see how the contact pattern was and how the diff was wearing and behaving.
If all was well with new diff centre bearings fitted the contact pattern was checked again to see if it was exactly the same.
I do this to ensure a quiet diff gear noise wise and try and keep manufactures specs.

Originally Posted by isuzutoo-eh

Mine did it till I had my centre diff reshimmed, hasn't done it since. Could be coincidental...

A worn driveline increases the distance the drive components travel when the diff unloads before they hit a solid stop - being the engine.

If travelling at a constant speed (any speed), and the diff unloads it forces the drive to over speed until it hit something solid, being the engine, which is now not turning at the same speed as the drive line. If you can picture a fixed shaft with a 100Nm load and all of a sudden the load let go, it will spring back in the opposite direction causing an almighty bang. You need to remember with a auto locking diff it is the inside wheel that drives in a corner, opposite to an open diff, so when the diff is driving on the outside and then lets go in a corner (or crossing a kerb, it hits the inside drive with incredible force and tries to force the vehicle faster, if you get it right you can make it bang back and forward continuously as the outside then the inside transfers the force back and forward. An auto will not have anywhere near the problem a manual will have, the torque conv allows the impact to be absorbed. A worn driveline will increase the perceived severity.

Someone said they had hytuff axles?????? I am on my third set (two MD and one something else) and the flanges are welded, they flog out splines because of the constant hammering. Waiting for 35 spline dana axles to go in. I currently have a nekarth locker that is smoother than a detroit, but is now flukked. Don't ever buy one. Compared to a detroit they don't last as long, actually thats not quite true, I have never worn out a detroit, so i don't know how long they last. The nekarth has probably done 60-7000k.

I have smashed a worn centre diff when my nekarth locker unloaded.

I haven't explained this very well. When new they can do it until you start to modify your driving style and the diff wears in a bit.

Actually best advice is don't buy an auto locker diff, use ARB, Ashcroft, Eaton, etc manual lockers. The number of times I have wished I could unlock my rear diff on a side slope has convinced me to fit a dana60 elocker to give it a go.

Looks like 101ron beat me with an explanation.