1972 "260" ujoint -to- 1977 "297" ujoint upgrade ?

[viking427]

Was given a set of front axles (longs/ujoints/stubs) out of a 1977 (Dana 44) Blazer front end that I want to put into a 1972 (Dana 44) Blazer front end to get the later style larger "297" u-joints. Its my understanding the stubs & longs are exactly the same dimensions (diameters, lengths, everything) and that only the U-joints on them are larger on the 73-77 D44 axles, thus it is a direct, no-headaches swap, but then someone said no, I also need the knuckles and spindles off the 77 since the 77 stubs are larger and won't fit into the smaller 72 knuckles/spindles. I knew the wheel bearings were larger in the 73+ spindles, but I thought the stubs were exactly the same dia. & length and only the u-joints were different. Can someone confirm the stubs are indeed interchangable and I don't need the 77 knuckles & spindles ? -thanks

[kwmech]

It is the back side of the spindle that is different where the outer stub seals. So an upgrade would be in order anyways. They will fit, but the newer stub has a rubber V seal that could become damaged on the older spindle. AND with the 77 spindle comes a larger inner bearing. So with that comes the hubs. Not a big deal it all bolts together and you n=have to take it down that far anyways. Knuckles nope, unless the ball joints are loose. 72 has what they call a 'flat top knuckle that can be machined if you want to go to cross-over steering and it also has a top taper tie rod end hole where as the 77 tie rod comes into the knuckle from the bottom. Either than that, the spindle and everything else will bolt up without issues

[turp mcspray]

FWIW, I have ran the newer axles in my 72 for many years with no problems.

[viking427]

Thanks guys. RockAuto shows the same part numbers for 72 vs. 77 "spindle hub seals" and outer "wheel seals", but different part numbers for the inner "wheel seals". I'm not sure what the official name of the seal on the backside of the spindle where the stub axle enters is called, but I suspect its the "spindle hub seal" I'll get a couple of everything, see what fits and return whats not needed.


1972
Front Axle; Outer wheel seal; Spicer 44-5F 8.5" R.G.
NATIONAL Part # 5778,
Oil Seal; Polyacrylate Seal, Shaft Size=1.552", Housing Bore=3.16, Outer Diameter=3.165, Width=0.53in

Front Wheel; 4WD; Inner wheel seal
NATIONAL Part # 442380
Oil Seal; Nitrile Seal, Shaft Size=2.5", Housing Bore=3.251, Outer Diameter=3.256, Width=0.312in

Front Axle; Spindle Hub Seal; Spicer 44-5F 8.5" R.G.
NATIONAL Part # 472397
Oil Seal; Nitrile Seal, Shaft Size=2", Housing Bore=3, Outer Diameter=3.005, Width=0.312in



1977
Front Axle; Outer wheel seal; Spicer 44-5F 8.5" R.G.
Front Axle; Outer wheel seal; Spicer 44-8F 8.5" R.G.
NATIONAL Part # 5778
Oil Seal; Polyacrylate Seal, Shaft Size=1.552", Housing Bore=3.16, Outer Diameter=3.165, Width=0.53in

Front Wheel; 4WD; Inner wheel seal
NATIONAL Part # 471271
Oil Seal; Nitrile Seal, Shaft Size=2.5", Housing Bore=3.251, Outer Diameter=3.256, Width=0.375in

Front Axle; Spindle Hub Seal; Spicer 44-5F 8.5" R.G.
NATIONAL Part # 472397
Oil Seal; Nitrile Seal, Shaft Size=2", Housing Bore=3, Outer Diameter=3.005, Width=0.312in

[1972CST]

They call it a spindle service kit. It comes with the needed seals and outer stub support brg. The spicer kit # is 706527X. This kit is for 73 and up spindle style (you will need the correct spindles for your new shafts to seal properly).

[Burt4x4]

The 297 axels slid right into my 72 with no mods needed...I believe the older D44 had the different spindels but I have no direct exper with that cuz my 72D44 accepted the axels just fine....