Hey all,

I have a '90 B250 with a A518 trans. I have a leak that is coming from the speedometer adapter on the side of the tranny, and I am planning on replacing the inner pinion seal as well as the adapter O-ring. I have the pinion seal, but I can't seem to find out which O-ring I need. What material/size is it? Does it matter (as long as it fits)?

I want to get everything together before I start, because I hate stopping mid-repair to go find something I need.

Thanks

 

You can bring the old O-Ring with you to the auto parts store and match it for one they will have behind the counter in their O-Ring assortment box. NAPA stores usually have these. Worst case scenario if you don't have the old O-Ring bring the speedo sensor with you and try different ones from the assortment kit until you find the correct one. Any rubber O-Ring will seal trans fluid from leaking as long as the speedo sensor is in good shape.

I think Harbor Freight has O-Ring kits so it might be worth a trip there for a look. You can probably buy a great assortment of O-Rings from them for under five bucks.