Snagger Posted December 28, 2009 Share Posted December 28, 2009 Hi folks, hope you had a good Christmas! I have replaced the pinion seal on a 110 Salisbury axle to be fitted to my 109. I marked the nut and pinion prior to removal so that the nut could be refitted to the original position, but while cleaning the parts for reassembly, the marks were washed off. So,I have checked the LR green bible, and it says that when fitting a new crush tube and setting the pinion bearing preloads, the crush tube needs a torque on the nut of approx. 250'lbs to start crushing, with the required torque rapidly increasing to continue crushing the tube until the preload is correct. I am reusing the original bearings and crush tube, and so far have just torqued the nut to 150'lbs. This seems tight enough to prevent it from undoing and to make sure that there is no play in the bearings (both bearings tightened right up against the crush tube), but should not have crushed the tube any more. The worry is that the tube may have a little hysteresis in it, expanding a touch as the nut was undone, and may not have gone back to the same length as before the nut was undone. However, after 20-odd years and well over a hundred thousand miles in place, I would hope that the heat and vibration in service would have relieved the compression stresses and set the tube length permanently. Does anyone know if leaving the nut at this 150'lb setting will be sufficient, or will it cause problems? Quote Link to comment Share on other sites More sharing options...
Lars L Posted December 28, 2009 Share Posted December 28, 2009 There isn't a torque tightening as such on a Salisbury. What has to be done is to measure the resistance needed for turning the pinion. The Green Bible states the value. Most of the time, there is sufficient play in the diff so the pinion can be rotated a little. I have recently had my Salisbury apart and I used a fish scale to measure. Since I'm metric I used the figure in kgf/cm by marking 10 cm on a ratchet and then tightened until I got 1/10th of the resistance given in the book. Quote Link to comment Share on other sites More sharing options...
Snagger Posted December 28, 2009 Author Share Posted December 28, 2009 There isn't a torque tightening as such on a Salisbury. What has to be done is to measure the resistance needed for turning the pinion. The Green Bible states the value. Most of the time, there is sufficient play in the diff so the pinion can be rotated a little. I have recently had my Salisbury apart and I used a fish scale to measure. Since I'm metric I used the figure in kgf/cm by marking 10 cm on a ratchet and then tightened until I got 1/10th of the resistance given in the book. Yep, I understand that. That preload (17-37inchpounds, IIRC)is set by turning the nut enough to crush the pacer tube between the bearings until the correct bearing preload is reached. The 250'lbs nut torque is the LR SIII manual's figure for the approximate torque required to start crushing the tube, well before the preload has been reached, with the torque required to further crush the tube increasing with the reduction in tube length. Since I am reusing the original bearings and tube, then the distances should not have changed and the preload should be right if the crush tube has no spring in it (ie. it hasn't lengthened again on release). I think that the crush tube should retain its original crushed length, given that it requires well over the 250'lbs starting force, and I'm working on the assumption that 150'lbs of torque on the nut will get the nut, bearings and tube nice and tight without increasing the preload to what it was before stripping. Quote Link to comment Share on other sites More sharing options...
Lars L Posted December 28, 2009 Share Posted December 28, 2009 Well, since you already don't know exactly what you're doing just see to that some force is needed to turn the pinion making sure it's not too loose. I don't know the effects of it being too sloppy... Quote Link to comment Share on other sites More sharing options...
Snagger Posted December 28, 2009 Author Share Posted December 28, 2009 Well, I'm only guessing at my work being OK - I'm looking for definitive approval or disapproval, really. It all depends on how much spring is in that crush tube. If it has none, I should be OK, but if it is springy, then I'm in more trouble. Loose pinion bearings could result in the pinion moving off axis, which would almost certainly result in stripped teeth on the crown wheel. Too tight and the bearings will overheat, expanding further until they seize... Quote Link to comment Share on other sites More sharing options...
Snagger Posted December 29, 2009 Author Share Posted December 29, 2009 Well, I pulled the half shafts and tested the pinion preload with it driving the diff carrier only. It's exactly the same as on the other stripped axle (I suppose the gear ratio doesn't make much difference when there is no resistance from the hubs and road wheels). So, it would seem that using about 150'lbs on the main nut if you lose the markings works well enough. Quote Link to comment Share on other sites More sharing options...
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