Lately i've been hearing some weird noises that i think is coming from the shaft drive. Its like a loud grinding/squeaking noise when i go in reverse. Does that sound serious?

 

is it coming from the rear end unit or the subtransmission (the oval that the the high/low/reverse lever attaches to)?

 

The 85-87 250 Bigreds don't have the hi/lo/rev lever. The problem is probably the u-joint in the enclosed driveshaft assembly. Check the rubber boot on the driveshaft assembly (where it connects to the transmission) for cracks or tears that would let mud and water get into the driveshaft, that is a common problem on the 85-87 models.

 

so if the rubber boot is torn or cracked what should i do, replace it? and if it was, how would i get all of the mud and water out of the gearcace? please respond

 

If there is a problem with the driveshaft u-joint, the rubber boot could be torn up or worn out and letting mud and water in. This is something that needs to be checked on these old machines, mine has never been replaced but I know of a few that have worn out and caused problems in the driveshaft assembly. This might not be your problem, but it is something to check.

 

If the problem is in the driveshaft and/or the boot is torn, it will all have to be disassembled anyway. I would probably try jacking up the rear wheels and rocking it back and forth to see if you can tell where the noise is coming from.