Shock question. Please point me in the right direction

I have used the 1 inch piston Monroe heavy duty shocks for years.

I have a 2008 Duramax and I thought my shocks were still serviceable until a section of bad interstate had it doing the porpoise dance. I replaced with a known brand that were decent for a short period of time, then back to the bouncing act. I finally went with a set of 'Bilstein 4600's' a year ago and my vehicle is now bounce free.

Bilstein 4500 or 5100

2x on Bilsteins.

The yellow and blue Bilsteins are what he wants, the 4600s.

again, I'll say the bilsteins. on my 2004.5 I installed bilsteins at about 10K miles. the difference was dramatic both loaded and unloaded. The factory shocks IMHO aren't valved well for either unloaded or loaded riding. The bilsteins are still working well on the truck (now our sons) at 200K miles.

When we got our 2015 I put bilsteins on as soon as I could get them. again factory valving on the stock shocks wasn't what I liked.

In both cases I used the HD yellow units. there is a firmer set for lifted suspensions or larger tires which the claim is a stiffer ride with stock suspension. I think the HD yellows are a 4500 or 4600 series while the blue units are the 5100 series.

Good info. Thanks

Another vote for Bilsteins

Twosown zero is right, 4600’s, not 4500. I like the 5100 better because they are silver zinc plated and look very nice in my wheel well compared to the yellow and blue 4600’s.
I had a discussion on the TC forum a while back about the difference since everyone seems to think you need a lifted truck for 5100’s. I ended up contacting Bilstein directly. They said order the 5100’s rated for 0-2” lift for non lifted trucks and they will work fine, and they do on 2 different trucks now. They also said they are the same inside.

Had Bilsteins on my Tundra and they were awesome. For my 2500 Cummins RAM I went with Rancho 9000XL with the adjustable dampening knob. Haven’t done a camping trip yet but one is right around the corner. We shall see.