Ok. So my 95 ford ranger needed new u-joints on back driveshaft. No problem. Done dozens of u joints. Figured as long as I had the driveshaft off, I'd replace pinion seal. No problem right? Too easy....or not. Got the flange off. Got the seal off. Replaced the seal. No problem. Except that I didn't do the most important steps. Didn't mark or measure anything. Stupid, stupid me. Put everything back together and drove it about 1/4 mile. Drives great when my foots on the gas. Take my foot off and the vibration from rear end is bad, real bad. After reading the service manual (after the fact), found out that most likely the pinion is way not torqued right. My question is where do I start since I don't have any base measurements to go off of. My plan b is to drive it about 8 miles to a good mechanic and have him unscrew my screw-up. Any advice would be appreciated.

 

Did u put the driveshaft back in the same position that it was in? If it’s off balance that will create a vibration... just a thought

 

Got it fixed this morning. Climbed under and checked everything out. The vibration was that I didn't have the pinion nut tightened down. Boy. Talk about not paying attention to detail. Don't know where my head was at. Anyway. Went to ford dealership and got a new pinion nut. Put the truck on jackstands. Then I used a little engineering, and took a 2 foot piece of 1 inch square tubing, drilled 2 holes same distance apart (3 inches) as the flange and bolted it up to flange while I used a 3/4 inch ratchet to tighten down the pinion nut to where it was tight against the thrust washer. Checked for freeplay. None. Bolted the driveshaft back up, and test drove. Perfect. Well, about as perfect as a 23 year old truck with 233,000 miles can be. Now onto the next project. Pulling the front axles and replacing the u-joints and seals there. Then back brakes, and it should be ready for winter.