Ruben-Ram5th 1500
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I was planning to do a transmission fluid change, 83700 miles. but I saw that I have a leak on my output shaft seal that needed to be fixed first. Before I take anything apart, I always do research to order the correct parts, get the right tools, etc. Well, I've been doing a lot of research on these seals, and the information out there is extremely limited, and there are no pictures. I found some vague information that kind of pointed in the right direction, and it almost felt like I was the only one with a leaky output seal. There is plenty of information for other brands, but not for this particular 8HP75 tranny. To make a long story short, here are the seal sizes, tools needed.
Mark the position of the driveshaft with the yoke. I used a little bit of white spay paint and it worked just fine.
I used 1400 sandpaper on the yoke to clean the area where the seal makes contact.
Guys, besides the research, this was very easy to do. A bit intimidating after cracking the tip of the screwdriver. The shaft is not heavy so I was able to do it by myself, and it took me a little bit longer since I was measuring the seals before removing anything. I just wanted to make sure everything fits before crossing the point of no return. With that, I'm not giving the step by step, but I'm sure the list of items needed will help you a lot. Pictures attached.
I hope this information helps you.










- Seal # 710487 from National Oil Seals: 1.598 x 2.476 x 0.394 (outer seal)
- Seal # 710671 from National Oil Seals: 1.496 x 1.398 x 0.205 (inner shaft seal)
- 34mm socket for the flange nut.
- Seal remover tool
- 15mm to remove driveshaft bolts
- Get a medium size flat head chisel, like a screwdriver size to remove both indentations of the flange nut. I used a flathead screwdriver and cracked the tip in between the shaft the nut LOL.
- Something to catch transmission fluid, some will come out. In my case, I had a few drips.
- Degreaser to clean area once you are done.
Mark the position of the driveshaft with the yoke. I used a little bit of white spay paint and it worked just fine.
I used 1400 sandpaper on the yoke to clean the area where the seal makes contact.
Guys, besides the research, this was very easy to do. A bit intimidating after cracking the tip of the screwdriver. The shaft is not heavy so I was able to do it by myself, and it took me a little bit longer since I was measuring the seals before removing anything. I just wanted to make sure everything fits before crossing the point of no return. With that, I'm not giving the step by step, but I'm sure the list of items needed will help you a lot. Pictures attached.
I hope this information helps you.









