wrong yokes on NP 205

[phoenix]

I had a little issue with the yokes from the NP 200 fitting on my NP 205. even though the chevy version of the NP 205 is supposed to have the 10 spline shafts, mine has 32 spline. I wasn't about to spend money on new yokes or those expensive ($22.00 a piece) conversion U-joints. I came up with a solution and thought I would post it just in case someone else would like to do the same and save some cash. here is the pic of what I did to modify my original 205 yokes. I drilled a hole and tapped it to 1/4 inch threads. I would lock tite these to be sure they don't move. I used a washer for a 5/16 bolt so I could shift it further over and bend it. I used a punch to bend the washer. Its kind of hack, but it should work with no problems and its way better than buying three new yokes. It will use the strap type clamps, so you still have to buy three sets of the clamp kits, but that is far cheaper than the conversion U-joints and you only need to buy the strap kits once. There is a conversion that will allow you to use a strap style yoke with U-bolts out there just so you know. all you do is drill out the threaded holes in the yoke and put in the special U-bolts that come in the kit. I believe that Four Wheel Hardware sells them.

[fisherman]

I hope it does work, that is something I would never do. When it comes to safety stuff, which in my opinion that is. I would spend the money and do it right. If it doesn't work it will probably cost you a whole lot more in damage to who knows what. I hope it doesn't cost you or someone else their life. Your not going to drive that on the road I take it.

[moosejr]

My concern with that would be that it would not be balanced, and would eventually shake the bearings apart. I agree withh fisherman, . not something i would do, . . .except for maybe a field expedient fix to get you home. . . might not be a real big issue on a front drive shaft if you have locking hubs, so it isn't spinning when you are running at road speeds. . ..

[randyscycle]

Two issues I see with it:

1) The joint may or may not stay centered in the yoke.

2) The yoke may have been weakened by drilling in the side of it.

Why didn't you just pick up three of the u-joints with the circlips on the inner side of the caps? That would have been less work and safer and $22 each is a lot cheaper than a long tow bill.

[dahoyle]

Definitely don't like that, for the reasons already stated. Just not an area that I would cut corners on.

FWIW, if the T-case has 32 spline yokes on the front and rear outputs, then it is most likely a divorced Dodge unit, and not a GM.

In any case, I hope it works for you, but if I was you, I would start saving for the correct yokes.

Doug

[phoenix]

I really didn't intend this to be a daily driver type mod, As I said, its kind of hack. but it should be fine for an off road truck like mine. Could it have been better? Sure, I could have made a custom piece of metal instead of using the washer.

As far as weakening the yoke, the hole is in a place that does not really affect the strenth of the piece. It is in compression due to the strap and bolts pulling it together. If it really needed to be indestructable strong it wouldn't have been made of cast iron. Ductile iron is way stronger and of course high carbon steel and forged steel are even stronger yet. There is little force pushing against the washers that I have in place. plus the straps and bolts are holding the caps also. on a yoke with the little nibs on them, do you really think that the little piece of cast iron is that strong? I measured the joint in the yoke with micrometers to make sure it was indeed in the center. as far as balance is concerned, I used the same lenth bolts and the same type washers. how balanced do you think it would have to be? I would think that the cast iron itself would have more imbalance than the slight difference in weight of the bolts and washers. look at a brake drum next time and it should have some weights on it. The truck has a top speed of 143 MPH or is that 43 MPH I think its the latter. Its a wood hauling truck and a plow truck for my 1/2 mile long driveway, not driven very often. I am not rich, (I live in nowhere Wisconsin) nor can I spend a lot on this truck. I have built everything myself including the engine and I am currently making my own wheels using Hummer rims. I have made a home made frame for my Jeep CJ7 and made custom width axles front and rear including making a Dana 60 full floater into a narrowed semifloating axle for the CJ7 with custom made disc brakes. I even made the custom STEERING rods and drag link. I do all my own work. Everything I possibly can. Yes, I know what I am doing, I have an engineering degree in Electronics and have taken many classes in the Mechanical side including Mechanics and Statics and Strenths of Materials classes. I have a friend with a full Mechanical engineering degree and thrity plus years experience, I will ask him his opinion and see if I goofed it up.

I agree buying new parts to make this work properly would have been best, but this truck is needed now, and I have no money left to spend on parts.

[fisherman]

I didn't mean to offend you. I was just concerned that you knew what you were doing? Sounds like it will work for your truck and it's intended usage. I just wouldn't bet my life on something like that on a daily driver or hiway usage. I wouldn't want to have anyone damage something or endager their lives from a mechanical snafu. It sounds like you are very capable and have the time to make things work when resources won't allow the perfect fix. I'm sure it will be fine for low speed wood haul and plow truck.

[BigWheelBob]

Just a quick reply, then I will leave this one alone.
Have you ever seen the carnage when a driveshaft lets loose? Oil pans, floor boards, fuel and brake lines, and anything elso that gets in the way, not to mention the transfer case, or diff outputs. Please just leave the shaft out untill you can round up the proper parts, you will save yourself some money in the long run. Plus the balance from the added piece to the shaft will not help the joints stay together great either.

[randyscycle]

There is little force pushing against the washers that I have in place. plus the straps and bolts are holding the caps also. on a yoke with the little nibs on them, do you really think that the little piece of cast iron is that strong?

There is a lot more force than you think there. I have personally, on three different vehicles, blown the caps out of the end of the c-clip type u-joints, tearing the u-bolts in one, and shearing the bolts in a strap type on the other two, under load on the trail. That was at low speed and low driveshaft RPM. Those yokes are engineered for strength.

Like the others, I wasn't knocking your work, but you did put it out there for opinions, and they are being offered.