Correct U-Joint Size??
 

Has anyone that has replaced their u-joint, on rear of driveshaft, know what the correct size combination is?? I know you might say to go to the auto parts store and they will tell you. However, I did that yesterday and went through every combination that they had in trying to find the correct one. They were either the wrong bearing cap size or they were too long. I can wiggle the u-joint back and forth about 1/4" inside the clamps. I've already looked up what parts stores have said was the correct size, but everytime I put them in they don't seem to be the correct size. I have a '99 4wd with the aluminum. driveshaft(I think). I've tried both the aluminum and steel driveshaft u-joints. It's like it has the wrong size in it or something like that. Been like that since I bought the truck. Don't know if any of you happen to know what size combination that you used.