Alright, so on my Cherokee I installed the Bilstein 5150's up front and really like them. I want to order up some shocks for the rear and not sure if I want to get the 5150's again or save a few bucks and go for the 5125's.

Is there a difference in performance between the two besides the extra fluid in the reservoir? Am I gonna notice any difference in performance or lifespan? Should I spend the extra money on the reservoir to get the chicks?

Basically, am I gonna kick myself if I don't get the reservoir? They would actually be a cleaner install without them and since the rear shocks aren't very protected it would be one less thing for a stick to come up and grab or something.

From what i understand, the reservoir is basically to add fluid to the system for cooling purposes. So, long, extended uses with lots of shaft cycles will heat up the oil to the point that is passes too fast, or fades. For on road use or slower offroad use, a non resi will perform just fine. As far as the Bilstein shock numbers, I'm not sure if there is a valving difference between the two. But, if valving is the same and your aren't doing any high speed offroad type stuff, the non resi should be just fine.

Someone correct me if I am wrong ...

Valving is the same between the two. The lengths are a little different and the 5125's actually fit the needed lengths a little bit better but not an issue cause I have to relocate the mounts anyways.

They are basically the same shock but the 5150 has more fluid. . just like Don said. You would only notice a difference if you heat them up (think pre-run). Even then, it would be a minor difference.

Would that affect life of the shock at all? I do often run some gravel logging roads around my place for slightly extended times. Got to get to the good shooting spots in short time and all ya know.

I very seriously doubt it. However, you can't deny the bling factor of the 5150s. ..

With your set p and how you run it,the non-res shocks should work great.

Alright, 5125's are ordered for the rear. Thanks for the input guys.