Another np203 Mysterious Popping Noise

blazink10

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My truck has the np203.It is fulltime 4wd.It has hi and hi loc low and low loc.If yours doesnt have the conversion kit then why do you need lockable hubs?
 

blazink10

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I believe previous owner did it to have cheap semi 2wd but I’m not one totally sure.
 

blazink10

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I understand the 203 has a differential to eliminate binding since there are new u joints and the front end has been serviced including wheel bearings coils it be that the differential just can only do so much it’s only a slight noise but I’m not sure what else it could be or is that the symptom of a bad lockout? I replaced one lockout cap on that side the other crumbled when I took it apart.
 

Turbo4whl

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86 k10 350th Np203
Recently a buddy and I tore down the front end and replaced axle u joints, all new ball joints, repacked bearings, and installed a new lockout hub on the passenger side. Trucks been driving great except I’m getting a popping noise from the passenger front when Turning on pavement it doesn’t seem to be felt though the wheel it sounds like the bad u joints before but it’s brand new so I’m clueless. Truck has lockouts and unconverted Np203 I run it in 4hi with hubs locked as I heard it’s harder on the ole 203 to run in hi loc hubs unlocked. Any suggestions would be great front end has been greased and is in good shape sorry for the long winded explanation I’m a bit new round here.

As previously stated, you can not drive a 203 with your hubs locked on a hard drive surface. When you make a turn the front axle always travels further than the rear axle. With the differential locked and you turn the the truck, axle shafts will twist inside the housing until something gives.

You could be trashing one of the new front locking hubs.

More likely, you are forcing the already stretched front drive chain to jump a cog in the transfer case. The reason you hear it up front is because the front drive shaft transfers the noise like a megaphone.
 

dvdswan

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@blazink10 just an FYI, when you quote someone, you can type below the brackets. it will appear as the reply above.

Since the PO installed the manual hubs, I would urge you to verify that the part-time kit was installed in the 203.
 

RoryH19

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@blazink10 just an FYI, when you quote someone, you can type below the brackets. it will appear as the reply above.

Since the PO installed the manual hubs, I would urge you to verify that the part-time kit was installed in the 203.
My 78 k10 has a 203 with manual locking hubs from the PO.
How can you verify the part-time kit is installed?
 

dvdswan

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My 78 k10 has a 203 with manual locking hubs from the PO.
How can you verify the part-time kit is installed?

If the truck moves in hi or lo with the hubs unlocked, its installed. I would suggesting to @blazink10 to verify that there are no bad parts. I probably should have stated to open the t/case up as these kits come in all sort of different types.

He's tried everything else, if one of the parts has gone bad or the chain is stretched repairs will be needed.
 

RoryH19

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If the truck moves in hi or lo with the hubs unlocked, its installed. I would suggesting to @blazink10 to verify that there are no bad parts. I probably should have stated to open the t/case up as these kits come in all sort of different types.

He's tried everything else, if one of the parts has gone bad or the chain is stretched repairs will be needed.
Thanks.
I have driven it several times with the hubs unlocked to move it around. It's a project so not much use. What I need to check is if the T-case is in "Hi" or "Hi lock".
 

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