[jaeger83]

I have to get some work done on my differential, it really bangs going into reverse. I have a '68 302 with a C4 transmission. I know the rear end is not original. The guy who is going to fix the slop has listed parts he needs but am not sure what rear end I have other than it is a 9". The tag reads as follows: WDM-CJ 9BD
2 75 9 356A
The shop that may have the parts doesn't know how to translate this. They have a differential kit which may have all I need though I have to find a fellow worker of his who is smarter or better motivated to tell me what's in the kit. Before I do that, want to be smart enough to tell him/her what rear end it is. He is using words like OPEN, SINGLE or DOUBLE PINION, etc. Appreciate any help anyone can give me. Incidently, parts I am supposed to get are: axle gears, spider gears, thrust washers, differential pin, axle and pinion seals and housing gasket. Mark

 

[daveboys]

I don't think you need all those parts. Usually on an 8 or 9 inch the backlash just needs tightened. IT grows as the bearing and etc wear.

 

[kevinstang]

My book shows tag #WDM-CJ as being for a 1979 Ford F100 or F150 1/2 ton pickup, 2.75 gear Non locking 28 spline 9 inch assembly.The 9BD is the date code for the fourth week of Feb. 1979 (1979 model). My book shows same tag number for 80-82 F100/150's only 31 spline.Looks like yours being a 79 should be 28 spline if original.

 

[jaeger83]

Kevin, thanks very much. Will remember you in my will. Mark

 

[DENVER]

If the back lash is off and needs adjusted you need to buy a ring and pinion too. If you adjust it, you will cause the gears to cut a new pattern and it distroy it's self. Are you wanting to stay with this ratio? If you need a complete center section I can help. I rebuild them for a hobby and for a living. Denver

 

[jaeger83]

Hi Denver,
Just came back from the one of the local Ford dealers. Looks like it is going to cost me about $350.00 CDN for the parts alone. I am certainly open to other options, what do you have in mind, remembering the main goal is to get rid of the bang when I shift into reverse? Mark