Post NV4500 swap with Detroit Bang Bang

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SquareRoot

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Since converting from the TH400, I have been slightly perplexed with the "feel" of the drivetrain. Since day one, I noticed considerable "feedback" for lack of words, in the way the truck feels. I have a low mileage, 14FF out of a CUCV with original 4:56 gears and the infamous Detroit Locker. Being built for toughness and sheer strength, I have mostly ignored the comments about the locker not being fun to drive on the street. I'm in the desert and don't drive on ice or snow, so no big deal. Yes, I have experienced the occasional BANG after a turn but that has become normal.

Now to my point. I was thinking I had a lot of slop in the drivetrain because it kind of loads up when I put it in gear. Kinda like its taking up some slack and maybe the parasitic drag of the clutch/syncros pre-loads the drivetrain? Its difficult to explain. All the U-joints are almost new. New clutch. Trans has unknown miles but, is quite and shifts perfect. New motor mounts. Trans mount looks good. I removed the front driveshaft for now and no change.

When I turn into the driveway at low speed (3-5mph) is when I get this loading/unloading clanking thing going on. Then it dawned on me why it's probably the ratcheting action of the locker being transferred thru the drivetrain. This makes sense. What really convinces me is I never felt this when I had the automatic trans in it with the same axle. I'm guessing that the fluid coupling (TQ convertor) absorbs that energy.

I am tempted to swap rear ends and put the factory one back in just to prove my point but that's a weekend experiment I don't really want to tackle. If I'm correct, the locker is coming out and I'll be shopping for a different kind of locker.

What ya'll think? Anyone else have this oddball (manual trans/detroit locker) combo and know what I'm talking about?

I'm going to go drive on some dirt here shortly and see if it changes anything. Maybe if the tires can slip a little in the turns it wont reverberate back into the drivetrain.
 

Bextreme04

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I just put a Yukon Grizzly in my factory 14Bff. I haven't gotten to drive it yet, but in pushing it around my yard it doesn't seem to have more drag in cornering, it just clicks in the turn.

I did notice that even with the backlash set correctly I get a solid 1/8" turn of the driveshaft before it tightens up in either direction.. which explains the clunk I always got when putting it into gear.
 

Vbb199

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Yukon duragrip all the way! Im running one in my burb's rear axle. its a clutch type with spring loaded plates... no clunk or hard noises when it engages, very quiet.

As long as im able, i wont run a mechanical locker in anything else on the street just for the sake of "smooth driving", however you already have a straight drive, and transfer case, so a mechanical locker like a grizzly locker really wouldnt make all that much difference in terms of drivetrain noise lol
Idk about those true tracks..... Ive heard a couple stories about them exploding.... i think @Catbox Might have a horror story also.

I am however running a grizzly locker in my s10's front d60 axle, but thats a dedicated offroad rig, and even with those meaty boggers, when a tire starts to slip, it takes at most a 1/4 tire rotation and it engages, but theres no audible noise or feeling at the wheel, and the best part is, unlike a ****** detroit, the grizzly locker disengages on a turn under power so you dont have that obnoxious torque steer and banging and ****.
 
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Frankenchevy

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As you know, I have the same setup. Yes the Detroit feels clunkier behind the nv4500 than the th400. I’m in the same boat. I’m swapping the Detroit for an ARB.
 

SquareRoot

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As you know, I have the same setup. Yes the Detroit feels clunkier behind the nv4500 than the th400. I’m in the same boat. I’m swapping the Detroit for an ARB.
Man I'm glad to hear that. I couldn't recall if you had the locker or not. Nice to know someone knows what I'm talking about. I'll look at the ARB. Thanks
 

Frankenchevy

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Man I'm glad to hear that. I couldn't recall if you had the locker or not. Nice to know someone knows what I'm talking about. I'll look at the ARB. Thanks
I came to the same conclusion about the TC. The auto absorbs that energy just like it absorbs energy going the other direction.

The Detroit is reliable, but unnecessary for almost all highway driving and harder on some other pieces on pavement. The ARB is supposed to be fairly reliable. From my research, most leaks are due to poor installation. I really only want it when needed for mud or snow on mild trails around my property and forest roads.
 

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