1999 4x4 3.0 V6
So I was getting some weird vibration when moving, generally once I hit 20mph, couldn't locate it at a standstill even when revving the engine so I took it in. They said the noise is coming from the transfer case and I would need to have it rebuilt for $3k. They said it was 1.5qt low on ATF fluid (which is the capacity of the t case), so as a hail mary before swapping it or attempting to rebuild it myself I decided to change the fluid on it. Well the bolts on the weight were super loose and when I took them out I could see some aluminum on the bolts threads, instantly knew the bolt holes were stripped. Changed the fluid anyway and got 1.4 qts out and it looks pretty clean. The bolts on the weight looked like they hadn't been touched in years which they would of had to remove to drain. Not sure how they determined how much it was low, they are closed on the weekends.

Could the vibration coming from the transfer case be the stripped bolt holes for the weight? Is it worth it to try and put some helicoils in? Before putting the bolts in I coated the bolts in "The Right Stuff" thread sealant in the hopes it would tighten them a bit.

 

Could have been if it was loose, just leave it off

If was ONLY for counter weight vibration in 4HIGH when above 40mph, in 2WD the front drive shaft won't be turning in your 1999
Most people never install that weight after a rebuild

You have a BW1354 transfer case they are very reliable so a used one is a pretty safe bet

Common vibration on 1998 and up Ranger 4x4s is the front drive shaft propeller joint, where it bolts to transfer case, these wear out often

 

I haven't switched it to 4wd in a while, this is only making the noise/vibration in 2wd. You're saying I should remove the weight and drive around and see if it still vibrates? Do you have any other suggestions to try as well before committing to the swap?

 

I'll try to help. A vibration can be many things but most common thing to check is the U-joints on the drive shaft if you haven't. Is the vibration felt in the Seat or in the steering wheel more? When you rule out all other possibilities of the vibration you can move your attention over to the transfer case.

First thing is the counter weight. Before you removed it was there play? The bolts are known to *break* there, but not strip out. This could be indicative of a violent vibration in the transfer case. Does it shift into 4x4? Try safely jacking up the rear end and spinning the tires with it in 2x4 and trans in nueatral. Listen for noise in the transfer case. Then try it in 4x4 with the whole truck jacked up. Does 4x4 even work?

Check for leaks around the transfer case and transmission. It could have leaked all its fluid and chewed itself to death inside if there was truly no fluid in it and the shop replaced the fluid. If that's the case you'd need another transfer case.