So a 203 t-case would tolerate a bit more driveline bind because of its chain driven system im assuming? I know some guys say that you can run different dif ratios with a chain style t-case.

Is this driveline bind the reason people do double transfer cases or "twin stick" transfer cases.

 

np205 divorced transfer case not full time all driveshafts look good have not sent them out for balance yet due to cost, In 2wd no noticeable issues , when in 4x4 its has the clunk/ shudder / bind does not seem to matter on road condition, planning a 7.3l idi swap so not to concerned as of yet but it is a issue for me at higher speeds, my truck has sat for along time and the previous owner was very young so trying to undo alot of poor work that has been done to the truck, getting there

 

It's not the chain but the differential in the np203 t-case that lets them run different ratios. Still hard on the t-case though.

I think they do the double transfer case to get the extra low range ratio.

The twin stick is a bit different where you can have separate control over 4wd vs 2wd on one stick and then low vs high on the other stick. It lets you do 2wd low. The old Scout had twin sticks and in 2 low, you could break axle shafts.

 

I think I'd pull the pto cover off the t-case and look inside. No problem with the hubs locked in at speed?

 

Try taking the front drive shaft off and drive in 4wd. Sounds grumpy=t-case problems

Also try the same with the rear shaft removed.

This is so Hi jacked, sorry Bryan.

 

NP203 is always under a slight bind. It has a differential in the t-case to allow the front and rear axles to turn at different speeds when in high and low. When you switch it to low lock or high lock the differential is locked together making front and rear axle spin at same speed. Thats when the bind is increased just like the np205 when its locked in.

 

Under no circumstances should you run a NP205 in 4WHI or 4WLO with hubs locked on anything like a dry road at any speed more than a few feet .... and even then likely have to back up to relieve tension that builds almost as soon as you move in 4WD.

As already stated a NP205 in either 4Wd position locks the front and rear driveshafts to exact same speed and even if you use the same gear ratios exactly (not all are the same, they are rounded to two decimal places, only if ring and pinions at both ends have same number of teeth as other end are they the same) and even with same tire sizes .... there is different loading and tire pressures that change rolling radius front to rear and then .... the front will track a larger arc in any turn than the rear axle.

And if you were to ever get all that to be the same, there's U-joint angles to consider, as a U-joint causes oscillations in operation when run at any angle other than straight, the input side can be steady RPM but the driven side will speed up and slow down twice each revolution and only averages the same RPM. The greater the angle, the greater the oscillation.

You should only run it in 4WD with hubs locked on surfaces that are slick or slippery where tires are free to slip and thus not put undo binding up loads on the drivetrain.

You can drive all day with hubs locked on a highway as long as the NP205 is in 2WHI.