Sorry if this is a repost, but I haven't found anything for this question. When I use jack stands to work under my car I place them under the frame rails. I just did a search and found recomendations to place them on the reenforcement plates where you jack the car up. I think that's a weird place for them since there is no grooves for the tips of the jack to fit in. The jack fits perfectly around the frame rail, so the weight of the car is resting on the thicker part of the jacks, rather than just the tips. Well it's time to change my oil and now I'm a little concerned if I'm doing this safely. Any advice??

Sorry if this is a repost, but I haven't found anything for this question. When I use jack stands to work under my car I place them under the frame rails. I just did a search and found recomendations to place them on the reenforcement plates where you jack the car up. I think that's a weird place for them since there is no grooves for the tips of the jack to fit in. The jack fits perfectly around the frame rail, so the weight of the car is resting on the thicker part of the jacks, rather than just the tips. Well it's time to change my oil and now I'm a little concerned if I'm doing this safely. Any advice??

on my 325, i use the front subframe to support it and on the rear, the side jack points. do a search for jack points. I have AC stands and the potato chip lips fit perfect.

You really want the jack stands under the stock jack points. That area is reienforced and is cabable of taking the weight of the car. On some cars a small pad need to be placed between the jack stand and the jacking point to keep the ears away from the rocker panel.