Rear end dipping

[Ghost]

Is there something to do to the rear suspension to eliminate dipping when using full acceleration ?

 

[jrSS]

Stiffer shocks and springs

 

[CaptainXL]

Many of us recommend the Bilstein HD's. You might want to check if you have air bags or springs. The air pump can go out or bags develop a leak.

 

[The_Roadie]

The air suspension was only an option on the Envoy, the TBSS, and one or two of the other four marques in the lineup. Not offered on the TB SWB or EXT.

 

[CaptainXL]

Thanks for that bit of info sir.

Ok then check for broken springs!

 

[hockeyman]

My rear left spring on my envoy is a bit weak. I've noticed that my left rear mudflap scrapes when entering a driveway with a minor slope. When entering from the other angle, the right side doesn't scrape at all.

Any recommended places for upgraded rear springs? I'm interested in stock height, or maybe slightly higher.
I'll look into a set of Bilstein HD Shocks too.

 

[The_Roadie]

Or take out the nitrous system that's causing the excessive acceleration.

 

[The_Roadie]

Any recommended places for upgraded rear springs? I'm interested in stock height, or maybe slightly higher.

GM, in their infinite wisdom, built these vehicles with at least TEN different spring stiffnesses for the front and another ten for the rear. If you know which ones you have (look for a paper part number tag on the spring), you can try GM suppliers for one higher on the stiffness chart.

Rockauto lists Moog, Rockwell, Raybestos, and ACDelco rear springs. If you want just a bit more stiffness, I'd install springs meant for an EXT, which wold be Moog 81051, for $57 a pair. Amazon has those for $52, but it's not clear if it's for a pair, with free shipping. Local parts stores should be able to order them if you're in a hurry.

Since there is a thriving market for folks with dead air suspension systems to replace them with spring coils, there are aftermarket suppliers of coil kits, but none of them offer the sheer variety that GM designed in. Most of them are meant for EXT/XLs, one size fits all, which are a bit stiffer than the normal short wheelbase (SWB) vehicle needs. 2007+ Tahoe and Avalanche springs also fit, and give about 1.5-2" of lift due to their stiffness, and many offroaders install these because they are WIDELY available for a low price on Ebay because they get taken off of new trucks that get lifted or lowered. I've gotten pairs of these Tahoe Z71 springs for as little as $20.

And if you ever tow, and need to adjust your height a bit, the most widely installed spring mod is Airlift 1000 bags inside the springs. Search for Airlift or Airlift1000.

 

[hockeyman]

Damn, thanks for all of the good info!!

I'm not really planning on towing, unless it's something completely unexpected. I'd like to get a bit more stiffness for the rear suspension, and a generic upgrade is fine with me. I'll probably get the Moog 81051's that you've recommended.

Summitracing has a set of Bilstein Rear HD Shocks for $133 shipped, and I already placed my order with them

Not in a huge hurry to install the springs, so I can wait a little while for shipping. However, I would like them installed before winter hits...

Again, thank you for the info!!

 

[Ghost]

Or take out the nitrous system that's causing the excessive acceleration.

Lol ! I love the acceleration on the i6 + my lead foot can't help it:thumbup: alrighty, so bilstien hd shocks is what i need. I hope it helps a little with the turns as well.