Vile & Depraved Timbrens Install

The following is a description of the Timbrens installation I just completed on my 2012 Suburban LT 4x2. Some folks will find this thread vile and depraved, as we will be showing the hard protuberances in the nether regions of one of Chevrolet’s finest as well as talk positively about the dreaded hard rubber Timbrens. There also is a topless photo of my trusty assistant for those of you brave enough to make it to the end. So if this is too much for you, give me an indignant gasp, clutch your pearls, and head for the exit!

Now on with the install!

This really is easy if you do 2 things. First, throw the instruction in the trash or use them to pick up dog poop, cause they are about useless. Second, search “timbrens install chevy” on the youtubes and there is a cool video that shows how to do this on a 2005 Chevy Suburban. It’s the same basic procedure I used on my truck.

For those of you who are unfamiliar, a Timbren is a product that is an alternative to using airbags on trucks and SUVs that experience rear end sag. It’s basically a hard rubber helper spring that goes in the place of the rubber bump stops found on most vehicles. On the Suburban, there is only one type of airbag that will fit – I tried that already – the Airlift 1000 – and it goes inside the coil spring. I didn’t like these things and there is another thread where I talk about that.

First you remove the factory bump stops. This was really easy – they just pulled right out. If you have a 5 year old neice or grand-daughter, she can handle that job for you.

As you can see here, the factory bump stop and the timbren are about the same height. But there is no comparison in the rubber. I don’t see how the factory bump stop would keep the suspension parts from crashing into each other as it is so thin and flimsy.

Once the bump stops are removed, you jack up the rear end of the truck to create some space between the axle and the bump stop cup:

You then push the timbren into the cup – you will be lucky to just get it in enough to stay in place. Put some pieces of 2x4 to act as shims. Watch out for any brake lines or other delicates – like wiring – are not contacted.

Then all you do is slowly release the jack. The wood helps compress the timbren and force it into the cup so that it is held securely. Then you jack the truck back up, remove the wood, and lower it back down. One side done. Here is a pic of the Timbren in place – it’s blurry, so sorry about that – but you can see it’s in place with about 1 -1/2 inch of space between the bottom of the timbren and the steel plate on the axle.

You do the same for the other side, and then you are done. I went for a drive around town, over bumpy roads and such and found no difference at all in the ride. Smooth and silky as always.

Next up – test towing!

First I measured from the fender lip to the floor – 37 7/8” as it always is.

Then I hooked up my Surveyor 189. As shown in another thread, this trailer has a 500# tongue weight. I took a pic under the truck with this trailer attached. As you can see, the Timbren is just making contact with the plate on the axle – doesn’t look compressed.

With the trailer hooked up, it’s 36-1/8” to the fender lip. So that’s about 2” of sag.

I then went out for a tow. Amazing is all I can say. The ride is as smooth as it always is, but now the truck feels like a firm, stable platform. Bumps and breaks in the pavement are a non-event. This picture shows me hooked up. I’m using the 5-1/4 drop hitch – think I’ll go back to the 3-1/2” drop so the trailer sits a bit more level.

Then I went back to the shop to hook up my Sunset Trail 25RB. This trailer has a 1000lb tongue weight and weighs about 7000lb loaded. Just for fun, I hooked up the trailer without the WD bars set and measured – 35-1/4” floor to fender lip. With the 1000# bars hooked up, I measure 35-5/8” – interesting.

Here is my WD setup. Look good?

So I went out for a tow with this trailer. Again, rode beautifully. Actually, I think this bigger, heavier trailer tows better than the smaller one. In fact, it seemed like I had much more reserve engine power. Must be the aerodynamics of the fiberglass front cap.

These pics seem a bit deceiving – looks like the truck is sagging more than it really is when you are standing by and looking at it. Anyways, 2” drop and stable handling characteristics - I can live with that.

Mr. Bonz, my trusty assistant, approves!