The first Model T Fords used what T collectors today call the “No Rivet” rear axle assembly. Ford made the two main pieces of the axle housing from deep drawn steel sheet. It was an engineering gamble to drive down the cost of manufacture.
The 1909 axle assembly had Babbitt bearings cast and inserted into the housing on each side of the differential. The drive shaft has a Babbitt bearing cast into the rear end of the drive shaft housing to support the pinion gear and act as a thrust bearing. It is cheap to manufacture but it presented many problems in service. First, the inboard bearings were impossible to replace without special tooling. Second, the housings tended to crack and bend easily. Third, because the assembly was not too strong, the bends and cracks led to leakage of the lubricant in a short period of time.
The drive shaft used an early version of the “two piece drive shaft” construction that Ford used until late 1913. The U – joint ball and the radius rod attachment are removable from the front of the drive shaft. This makes for easy installation and removal of the pinion bearing. The pre – 2500 parts are somewhat different from later assemblies.
Forward end of the two piece drive shaft 1909
Rear of the drive shaft shows no pinion bearing housing as found on later Model T’s. The pinion bearing is poured in the drive shaft and machined in place.
The outer backing plate on the rear axle provides a place to mount the brake shoe, attach point for the radius rod, and the brake actuating cam at the top. In 1909 this plate was flat and plain on both sides. Not that this photo shows a later tapered axle. The early cars did use a Hyatt roller bearing at the outboard ends of the axle.
The axle shafts used in 1909 are 1.0625″ diameter forged vanadium steel machined the full length. It uses a keyway to transmit driving motion to the wheel hubs. The wheel is retained by a pin. The pin is held in place by the hub cap. All in all not a very good design. The cast iron hubs tend to wear in the pin holes and key ways, leading to a loose wobbly wheel.
The above photo shows a 1909 – early 1910 Model T Ford rear wheel hub compared to a late 1911 – 1927 wood wheel hub. Notice the rear hub is styled like a front hub. The outer flange of the 1909 hub is only 5 1/2″ in diameter. The 1909 hub used 5/16″ diameter wheel bolts that did not have a square shank.
View showing the inboard side of the 1909 – early 1910 5 1/2″ diameter rear wheel hub.
The front wheel hubs (above) in 1909 were 5 1/2″ diameter and used the same 5/16″ diameter bolts as the rear hubs. Note the early “block” Ford script hub cap used in 1909 – 10.