| Author | Message | ||
     Scott Ritzer (Truck603) New Member Username: Truck603 Post Number: 25 Registered: 07-2003 |
When I deside on my lift and start to have problems with vibs from shaft angles can I put on factory u-jointed drive shafts instead of going with a GB shaft? I know, don't scimp on this but I can get a LR rear u-jointed cheep and I presently have that roto-flex thing. My front shaft is u-jointed but not a dbl. cardon shaft. What are the thoughts. I am thinking of the Grn. Monster 2"or3" springs. Just trying to keep costs down to pass it by the wife. Thanks again. | ||
| Mark Devereux (Groupw) Member Username: Groupw Post Number: 116 Registered: 12-2002 |
You probably don't need to change anything if you stick with a 2 inch lift. It changes pinion angles and castor a bit, but in my experience not enought to cause vibes. 3 inch lifts are a different animal. 3 inches will change the front pionion angle and wheel castor significantly. Your stock front shaft probably won't be able to handle the angles. Problems may get worse with correcting the castor. If you do it, you create a greater difference between pinion angle and T-case shaft angle. The fix for that is a new front shaft with CV style joints at both ends. This shaft is short, heavy, expensive, and hard to balance. Rear 3 inch lifts also create some geometry problems. Since your axle drops in an arc, lifting 3 inches moves the axle toward the front of the vehicle. At rest, your stock rear shaft is essentially shortened and often completely compressed at the slip joint. This translates into vibes and lots of stress on bearings. Lift also changes the rear pinion angle, pointing it upward. You now have unequal angles at each end of the shaft. Unequal angles require CV style shafts. You can correct the pinion angle and put your axle back in the proper position with new trailing links from rovertym. You still may need a new shaft though. Stock rover shafts have 20 degree flanges and weak u-joints. Stock (3 degree) pinion angles on a 3 inch lifted truck will result in a resting shaft angle of 12 to 15 degrees. Lots of stress on u-joints and possible binding with articulation. (Ever break a u-joint on a trail??) Bottom line, your truck is a system and no change exists in isolation. Some people get away with stock shafts on 3 inch lifted trucks, but to my mind, this is a recipe for disaster. They are not made to handle the load. BTW, tons of good driveline tech informatin on Tom Woods web site. www.4xshaft.com |
