rubber sounding squeak when in reverse with clutch engaged?

Im new to this site so i hape this is the right place to post this. so when i am in reverse with the clutch engaged there is a rubber sounding ,rythmic squeak squeak squeak squeek, that accelorates as i do. then as soon as i let off the clutch, its gone. it sounds like its coming from the rear end some where. the seal where the drive shaft enters the differential is going bad because there is a small amount of oil around that area that is semi fresh. idk if that has any relation but thought id throw it out there.

Do you know if the rear end has oil in it now? Has is all leaked out? This is the time to take a quick look because it's obvious the seal has to be replaced pretty quickly.

First thing I would do is check the fluids in your rear end and trany by removing the oil fill bolts and stick your finger in the bolt holes to check levels. You can smell the oil for burnt smell at this time. If they are low, refill them soon as possible until the seal gets replaced. A seal is an easy fix, but replacing rear end or trany is a bit more difficult.:)
You have diagnosed most of your problem by spotting the bad seal. There is a reason the seal has started leaking most of the time. The seal could be old or it could be a universal joint making shaft wobble and damaged the seal or the center support bearing is bad. When any of these start to go, they will wobble and cause seals to be damaged and leak. You 1st need to find out if it has dumped all the oil out completely or to a point it is starting to damage bearings. So far it seems that reverse is only effected which isn't too bad yet
While your under your truck, you might as well check that center support bearing at the drive shaft split. Push up the driveshaft and check for sagging or damaged rubber. If it seems ok, pump some grease into the bearing through the hole of the assembly. Don't be shy about using too much either.
You can also adjust the clutch if this seems to be a little of an issue by going into the engine bay and against the firewall is a cable with a sort of spider gear nut and rubber grommet. You should be able to grab the cable housing and pull towards the front of the vehicle and have about an 1/8in. of gap as you pull the clutch cable away from firewall. If not familiar with this check, pretend you want to pull the cable out of the driver's compartment into engine bay by grabbing the outside of the cable housing. This cable should pull enough to show a gap between the rubber grommet and spider threaded nut. If not, spin the nut enough so you have about an 1/8in. of gap in there. There is a little nub on the rubber that locks the spider nut from spinning randomly.
Squeaking could be a throw out bearing going out or universal joint needle bearings, depending where the noise comes from and when it sounds off.
By all means you should have the seal replaced and refill the dif and the trany. The oil drain bolts have magnets that can show you any metal that has been collected if damage is done. Depending on the age of the truck and all, it is definitely time to check the above items.

It could be the drive shaft center bearing. It has rubber holding it in place.

i will difinately be replacing the seals and i will check the oil tomorow and see if there is a clue there. hopefully nothing too big, the clutch needs replaced and is slipping a lot so i might do the seals clutch and whatever else then.

It makes it in reverse? lube up the U joints, it will stop.