GMC AXLES and wheel question?

[cnoswalt78]

OK so every one who knows anything about them?
post what or how your using them?
early and late
any info would be good(lots of people use them but we have no knowledge about them)
ANY INFO! GOOD OR BAD!



im running 50s cross hatch cover with eyes on the axles 6.17 ratio and tranfer reverse rotation front axle.
2 wheel reverse and 4 wheels lock forward.

[BigFrank]

so mine are 1940  the drag link is on the rear of the front axle  my t case has two shifters and seems to have both outputs spinning both ways forward and reverse  my truck is a  g506 version that was a 4x4 not a 6x6  the axles seem to have a lot of slop between the pinion and ring gear probly from being used since the 40s

[cnoswalt78]

1 ok they aparently come chevy high pinion and need the tranfer case, or rotate to low pinion and shorten one axle... or flip  to low pinion on ford side and need no mods
2 and chevy got contracts for 1.5 tons & gmc got 2.5
3 gmc axles are alot bigger than 40s gmc axles aparently (mine are fine spline) what are yours?
4 ok and if you have yokes you have 6.67 gears and if you have flat flanges you have 6.17 (like mine)
5 ok and aparently you can run up to 66s without problems
6 and everyone says never weld fronts only rears
7 and gmc axles dont take as much power and stronger than rocks they say?any input?
8 and gmc's are rated 3 tons
9 ww2 axles will inter change with newer ones (like mine) but shaft size is big difference in newer ones
ill see if i can dig more (there was a guy who did one for a ford cant think of what the name is)

[BigFrank]

so mine are 1940  the drag link is on the rear of the front axle  my t case has two shifters and seems to have both outputs spinning both ways forward and reverse  my truck is a  g506 version that was a 4x4 not a 6x6  the axles seem to have a lot of slop between the pinion and ring gear probly from being used since the 40s

pinion on pass side high  shafts on rear have huge square splines  same as front  my truck was rated 1 1/2 ton  but they look the same as any other gmc housing accept the slite differences

[MR NASTY]

anyone know if the make a locker for the fronts???

[cnoswalt78]

ok military vehicles magazine feb 2009 has a article (A CLOSER LOOK... CHEVROLET G-506 1-1/2-TON TRUCKS)
banjo axles of ww2 have cast reinforcements in the cover(stronger than split axles) but a bit crude but did the job for over a half century. the disadvantagees of banjo axles include higher unsprung weight and the inability to stand up to high speed use. ok chevy had 6 louvers on the engine side panels gmc had 12, early gmcs had a small name plate welded to the grill.
G-506s had chevrolet stamped into the front 2/3 of the engine side panels, later the military decreed no more company names at all. Chevy frames stop at about the radiator a frame extention was riveted to the main frame on all trucks,so that the front spring shackles were attached to it and not the main frame itsself,if the truck had a winch the sub frame was longer chevy had 9 foot beds gmc had 12'

[BigFrank]

ok military vehicles magazine feb 2009 has a article (A CLOSER LOOK... CHEVROLET G-506 1-1/2-TON TRUCKS)
banjo axles of ww2 have cast reinforcements in the cover(stronger than split axles) but a bit crude but did the job for over a half century. the disadvantagees of banjo axles include higher unsprung weight and the inability to stand up to high speed use. ok chevy had 6 louvers on the engine side panels gmc had 12, early gmcs had a small name plate welded to the grill.
G-506s had chevrolet stamped into the front 2/3 of the engine side panels, later the military decreed no more company names at all. Chevy frames stop at about the radiator a frame extention was riveted to the main frame on all trucks,so that the front spring shackles were attached to it and not the main frame itsself,if the truck had a winch the sub frame was longer chevy had 9 foot beds gmc had 12'

mine is definetly a chevy then good info thanks

[marshall]

my brain hurts, but i think i just learned something!

[page69]

that was helpful info, that just means i can build my truck bigger!!!

[cnoswalt78]

what size tire is everyone here runninor planing

[page69]

i'm runnin 14.9 x 26s and 1600 x 20 michelins. my brother in law is runnin 18.4 x 26s on his gm axles.

[cnoswalt78]

67x34.00-25 tires have very big lugs where do i get wheels,
and 700x26.5 terigater tires (flotation) where to get wheels
plan one one of these and 1600x20 xzl's
all need wheels

[page69]

go to a tractor bone yard they have all that stuff.as far as the 1600 x 20 we used old concrete truck wheels.i took a set of old dodge 6 lug wheels drove the rivets out with an air hammer and they slide into the 18 x 20 wheels then tru them and weld them in.

[page69]

u can prety much use the centers out of any six lug wheel as long as u can take out the centers

[cnoswalt78]

what are the chances of getting them off a little?
and do they have to be rivit wheels, how hard is it to take welded ones out?
and will a waterjet cut stait enough for centers if nothing else.
I dont supose its easy with a torch hu, or will it warp, what about welding it in without warping it

[Kyle]

my brain hurts, but i think i just learned something!

[page69]

the rivet wheels are easy to get the centers out of.u just grind the head of the rivet off and take a air hammer and drive them out then just hit the center a couple times and they fall right out.i never tryed the welded ones.they might be easy i don'y know.pretty much any old six bolt wheel will work as long as the split ring is on the back.u can also us the centers in them dayton 22.5 semi wheels and run any semi tractor tire also.they got to have the raised center in them then just wend them in.as far as warping just take your time u want them as strait as posible.if u go with 24 or 26 inch tractor wheels u can drop the whole rim in minuse the snap ring and gust weld them in to thats what i did for my tractor tiresjust make shure they are centered in the tractor wheel then weld them solid.

[cnoswalt78]

sounds complicated! I dont know? build wheels that would run true? you guys must have more faith than me!

[page69]

theirs guys around hear that can build a wheel for 44s that balance out damn near 0 on a tire machine.just take your time tack every time then spinn it on the truck tweek it then weld it.

[BigFrank]

need is the mother of invention