Expansion plugs and pinion seal help

[WikedPlymouth]

Good morning,

I'm working on my 1959 Dodge Coronet. I ordered a pinion seal from Rock Auto and was sent a National 5126. This seal has an outside diameter of 2.81 where as the original was 2.74. I could feel and see that the replacement was actually larger but I tried to install it anyways but no luck. I checked a few other places and they recommend the same National 5126. Does anyone know the part number for the correct pinion seal to fit a 1959 Dodge Coronet with a 326 engine?

Also, I'm replacing the expansion plugs in the 326 engine from this car. The original expansion plugs measure 1.61 (assuming that is the same as a 1 5/8 plug) but seem to be a flat disk (see picture). I'm not sure where to get these from as my local Napa store wanted to sell me the standard plug with a thick edge. I did find a zinc plug at Grainger part number 5MTN7 which looks like it could be it but wanted to see if anyone else had any thoughts.

 

[john-9]

if you can measure correctly the original seal O.D. ,, the bore on the case where the seal installs and the I.D. of the seal (use the surface area of your pinion yoke where the seal runs ) i may be able to look up the seal number as i have a couple old CR seals cross reference books here . as far as the expansion plugs a modern O.D. equivalent of the original should fit.

 

[WikedPlymouth]

Thanks for the comments. I measured the O.D. of the yoke and it measures 1.873. The national 5126 had the right I.D. of 1.875 (just not the correct outside diameter). National 5126 is 1.875 x 2.813. My old pinion seal measured 2.744 for the O.D. So, looks like I'm looking for a 2.75x1.875. Just surprised that Rock Auto lists this as the correct pinion seal. I did try 2 of these and neither worked. Both bent as they could not compress that much.

 

[Jakter]

Autozone shows two different seals.
One for 83/4" ring gear and one for 8 1/4' ring gear.

 

[john-9]

if your measurements are correct you left out the thickness/width but i found 2 seals that should work and are available CR 18661 1.875 shaft diameter - 2.750 bore diameter - 0.313 width/thickness and CR18662 1.875 shaft dia. - 2.750 bore diameter 0.500 width/ thickness ,,, they both have Nitrile seal material and bore tight on the O.D. of the seal ,,, Timken uses the same number and you should be able to get them at any parts store. these old seal books have helped me numerous times the internet isn't as user friendly.

 

[WikedPlymouth]

Thanks so much for the information. I did go back and measure the original pinion seal. The top ring had peeled off but the remaining section measured 0.375 so I'm assuming with the top lip it would be 0.500 thickness. Looks like the CR18662 should be perfect. Thanks so much for the help!!