sorry , gl4 is API Gear lube@ 4 for gear boxes, M/t
the fluid (lubes) get dark for many reasons, non good.
full of metal dust.
water ingress. contam.
or someone mixed lubes, or additives.
just way too old, (time, heat, and the constant shearing action of the gears.)
i was just guessing GL4, the owners manual shows what it really needs.? but see below.
most boxes uses GL4, or and Some AFT, and others use 10w-30 engine oil.
in fact, some motor cycles the gear box and engine pan are all one in the same. (it's a crash box , no syncho's at all)
some gear boxes have special synchro's just so they can run , non GL4 lube. (YOURS?)
87 honda civic, m/t box. ill quote the FSM. (need one they are free for honda's)
"On the Civic manual transaxles, use an engine oil labeled for SG use or better. Use 10W-30 or 10W-40 viscosity; the 10W-40 viscosity is the safer recommendation, especially if you expect to be driving at highway speeds for prolonged periods in hot weather.'
ever seen this neat place. lots of free manuals.
http://hondatech.info/downloads/Auto/Manuals/Civic/
maybe someone put GL4 into the box, not knowing the correct lube to use.
this would top my list.
on a strange car I never attempt to guess what's there, i drain it and put in the correct lube.
the fluid (lubes) get dark for many reasons, non good.
full of metal dust.
water ingress. contam.
or someone mixed lubes, or additives.
just way too old, (time, heat, and the constant shearing action of the gears.)
i was just guessing GL4, the owners manual shows what it really needs.? but see below.
most boxes uses GL4, or and Some AFT, and others use 10w-30 engine oil.
in fact, some motor cycles the gear box and engine pan are all one in the same. (it's a crash box , no syncho's at all)
some gear boxes have special synchro's just so they can run , non GL4 lube. (YOURS?)
87 honda civic, m/t box. ill quote the FSM. (need one they are free for honda's)
"On the Civic manual transaxles, use an engine oil labeled for SG use or better. Use 10W-30 or 10W-40 viscosity; the 10W-40 viscosity is the safer recommendation, especially if you expect to be driving at highway speeds for prolonged periods in hot weather.'
ever seen this neat place. lots of free manuals.
http://hondatech.info/downloads/Auto/Manuals/Civic/
maybe someone put GL4 into the box, not knowing the correct lube to use.
this would top my list.
on a strange car I never attempt to guess what's there, i drain it and put in the correct lube.
http://www.fixkick.com