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Tom Wood's Custom Drive ShaftsNew Short Shaft Kits From Tom Wood For 231 and 249 Transfer Cases


With other budget tail shaft conversions, the method of shortening the main shaft while still installed into the transfer case is nothing that I would attempt myself or recommend to others. Although others have claimed success, I would think it to be very difficult to cut the shaft without heat warping the shaft and also maintaining the precision for squareness required for the most secure retention of the out-put flange. Additionally, a precise drilling & tapping of the shaft would be difficult at best. I have seen many shafts ruined in this attempt.

Many people seem to have some reluctance with the idea of tearing into their transfer case. The conversion requires nothing more than a partial dis-assembly of the transfer case, with a re-assembly in a like order with a couple of different parts. This can easily be done while the transfer case is still in the vehicle. The tool list is minimal and for most people, I recommend you allow 6 hours time to do the job. Many will get back with me and claim it only took about 4-1/2 hours. I think this is reasonable, and certainly a reasonable investment in time to insure a high quality, long lasting modification.

On other conversions, Axial float of the rear out-put flange is controlled only by the rear retaining bolt & washer. Between the flange splines and the splines on the out-put shaft there is a minor clearance fit. This minor clearance will allow for independent movement between the flange and the out-put shaft. Over time (sometimes very short) this will wear down the splines on the out-put shaft and the splines in the bore of the flange. This will eventually lead to the flange fitting loosely and letting the flange running eccentric. This will create vibrations and noise.

With our new kit, the out-put flange or yoke is securely "sandwiched" between the retaining washer and the rear out-put bearing on the transfer case.

With other lower priced tail shaft conversions you will have a significant unsupported shaft past the rear out-put bearing. This is of importance because under load your drive shaft will have a tendency to want to straighten out. This will substantially increase the overhung load (radial forces on the out-put shaft) and in high torque situations actually bend the unsupported out-put shaft.

With Tom's method, modifying the out-put shaft is done exactly the same as another famous and well proven conversion. Effecting the same net length change on the drive shaft and the main shaft of the transfer case. The significant cost savings is a result of modifying the stock bearing retainer rather than having to manufacture a new bearing/seal retainer and not replacing the more than adequate original rear output bearing.

Prices for the conversion package complete with the drive shaft are as follows:

With top of the line, long travel booted slip & spline CV drive shaft.....................$415.00*
With a solid premium quality component CV drive shaft....................................$385.00*
Including a "generic components" CV drive shaft. ............................................$345.00*

*These prices include freight (UPS ground Continental US) The price does NOT include a $200.00 core charge for the original main shaft & tail cone. Once you have the conversion done , simply give us a call & we will arrange for UPS to come by your door to pick up the core for return freight at our expense and you convenience.

In order to build the drive shaft to correctly fit your vehicle we will need a measurement from the vehicle. If you have a TJ or a later model Cherokee with the rubber boot that attaches to the slip yoke on the drive shaft, measure from the slinger on the rear out-put of the transfer case (This will be the leading edge of the rubber boot) to the center of the universal joint at the rear differential. If you have a Wrangler or an earlier Cherokee, Simply measure from the outermost lip of the rear out-put seal on the transfer case to the center of the joint at the differential end. From this original dimension we will be able to determine what the required length will need to be as an end result after you complete the conversion.

You will need to supply: oil for the transfer case, a small amount of silicon, and possibly shims for the rear differential. With the CV type of drive shaft it is very important that the rear pinion and the drive shaft have the same slope within 3 degrees. Or with a TJ or a Grand Cherokee with coil spring suspension, you will need to have a set of adjustable trailing arms.


For further information, contact:
Tom Wood's Custom Drive Shafts
306 East 31 St., Ogden, UT 84402
Phone: (877) 4xSHAFT