Hey all. My bronco is a 93, 351w with e40d auto. I bought back around christmas. I'm having two nagging issues. 1) every since I bought the truck, it has"slow-started (like a weak battery) the guy I bought it from assured me it was starter. I had starter tested= perfect. Then a month later (tranny went out), I had it tested again, and once again = perfect. I decided to leave it since it just an old truck & toy & not my daily driver & the fact, it always starts, just drags a bit doing so(atleast until yesterday). But then yesterday, I drove it about 20 minutes, went to girlfriends. Let it sit about 10 minutes. Started again and moved it to hook up a trailer, let it sit about 5 minutes went to start back and nothing. I tried my jump starter-nothing. After about 20 minutes of messing with, my girlfriends step dad finally help me get it started with a big battery from some of his equipment. I drove it about an hour, brought trailer back to her house. And once again, after sitting about 5 minutes, nothing at all. This time jumping starting was also a failure, We looked it over real good, figuring probably battery, but he just so happened to move the ground wire just a bit and instantly all the interior lights came on bright, it almost started, but battery just wasnt there, but this time it jumped off, no problem. The previous owner said his buddy rebuilt the motor about a year a before I purchased, I believe this is true, by the way it runs and no smoke or anything.So, it is possible, he could not gotten a groud connected back right or something. ONce I got home. I turned off the truck and it started back several times. So, the ground could possibly be the culprit to both issues, but should I be looking for anything else??
2) I also have a roar coming from what appears to be the right side, it started about a month after I did the tranny swap. it sounds distinctly like tire noise from an aggressive tire, but I have all terrain tires and htey have never made an sound before. I also had the entire front end rebuilt by a local suspension store. The roar is really evident after 45 mph, not really so much before and when it starts, i have some vibration i can feel in the gas pedal. a buddy of mine who retired from a local ford dealership said it kinda sounded like the pinion gear, and that the sound is traveling the driveshaft and that is why i hear it the front. Possibly, but i also wonder, would the little axle bearing you guys talk about all the time also cause this? Maybe suspension shop neglected it? Thanks guys
sorry about the length, just wanted to make sure the pros had enough info(lol)

 

Have your batery tested, but I'm 90% sure its your cables. They tend to rot internally at the terminals. You should try and replace the terminals (cheap/quick) or do the whole cables (main power and ground, a bit more involved).

As for the vibration, I'm not sure but I would get under and have someone bump the steering with the truck off and see if anything moves out of place. Odds are if you had the "front end rebuilt" it was just the hubs out. Doubtful they thought of the axle pivot bushings. This issue needs a bit more investigating.

 

An easy way to prove/disprove a suspected ground issue, is to use jumper cables as a temporary "new" cable. Connect one side of the cables to the ground post on the battery, and the other to a good metal point on the engine away from moving parts. If the problems go away, you know you have a ground problem.