railway express truck rear end??

AA Ford Discussion Group relating to the repair and restoration of your AA Ford.
Post Reply
davedd
Posts: 34
Joined: October 22nd, 2016, 1:25 pm
Body Type: aa
Model Year: 1928

railway express truck rear end??

Post by davedd »

I have a complete 7-1928 rail way express AA truck in very good condition, trying to find out what rear end it has no A or b casting marks it has a small symbol than an F bellow that TT2. ANY CLUES??
1wonton
Posts: 157
Joined: August 31st, 2013, 4:37 pm
Body Type: Express
Model Year: 1929
Location: Vallejo, Ca

Re: railway express truck rear end??

Post by 1wonton »

Pull the speedometer drive gear, the ratio will be stamped on the end.
davedd
Posts: 34
Joined: October 22nd, 2016, 1:25 pm
Body Type: aa
Model Year: 1928

Re: railway express truck rear end??

Post by davedd »

5 17 ?
User avatar
Neil Wilson
Posts: 3062
Joined: February 5th, 2003, 9:42 pm
Body Type: 82-A/89-A
Model Year: 1930
Location: Boulder, CO
Contact:

Re: railway express truck rear end??

Post by Neil Wilson »

davedd wrote:
February 3rd, 2018, 4:23 pm
I have a complete 7-1928 rail way express AA truck in very good condition, trying to find out what rear end it has no A or b casting marks it has a small symbol than an F bellow that TT2. ANY CLUES??
The first AA's came with the 5.17:1 high speed worm drive rear axle (not markings since there was only one gear ratio). The speedometer driven gear is a good indication that the axle gears are 5.17:1. After this many years, the internal gears could have been changed.

If the rear axle is still assembled then the following procedure can be used to determine the ratio. Turn one rear wheel (with the other held stationary) for one turn and count the number of times the drive shaft or engine turns over. If you are counting engine turns, then make sure the transmission is in high (which is the 1:1 ratio or straight through position for the transmission). The count of turns times two is the axle ratio.
A 28/29 worm and bevel, high speed axle will result in slightly over 2-1/2 turns of the drive shaft to make the 5.17:1 or 5.11:1 ratios. When the drive shaft turns over 3-2/3 times the axle ratio is a low speed.
Regards, Neil Wilson
______________________________________
aafords.com@gmail.com - use this email for contact
https://aafords.com/
Post Reply