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Old 04-06-2003, 04:31 PM   #1
CustomChevy
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Join Date: Nov 2002
Posts: 462
Lowering Methods and Information

I have seen some people ask about lowering and how to do this to their trucks. I thought I would forward my personal info on this topic.

Front End Lowering

For starters, I will cover only coil spring front suspensions. There are several methods to lower the front end of your truck. These are listed below:
1. Shortening the coils
2. Drop spindles
3. Drop lower a-arms
4. Adjustable coil-over conversion
5. Air Bags
6. Hydraulics

These are the most common methods to get the front end in the weeds. The last 3 methods offer the most versatility. Also remember that these methods can be combined to acheive final ride height. Don't forget to buy new shorter shocks for your truck after lowering!

First, shortening the coils can be accomplished in several ways. The coils can be heated, which will cause the coil to drop and lower the vehicle. This is done with vehicle at ride height with no supports. This is also the absolute WORST wasy to lower the front. The heat ruins the spring, bottomline.
Another way to shorten the coils is to cut the coils. To do this, the springs must be removed from the vehicle. Depending on your tastes, secure the coil and cut it to the desired length. It should be noted that you should only cut the MINIMUM amount off the coils because the ride will be affected alot if you cut too much. The spring rate does not get adjusted, and if too much is cut, then you will have a very "bouncy" ride to say the least. Best to cut only 1-2 coils.
A more expensive, but cleaner way to shorten the coils is to buy them. you will have new coils with desired ride height and also correct spring rate. These help to keep maximum ride quality.
Final note on shortening coils is that you will most likely need to have your alignment check and corrected after this procedure.

Drop spindles are a great way to remove 2-3 inches off of your ride height. These are also more expensive. This requires a bit of work on your part because there is a lot of pieces that need to be removed and unbolted to finish this task. However, this is a great "bolt-on" way to drop your truck. Requires no alterations and no alignment. Simple swap out and you're done!

Dropped lower A-arms have the spring cup lowered so tht the spring sits lower overall. It allows extra travel for the original spring and hence, the front is lowered. Just remove the old a-arm and replace it with the new one. Requires some work on your part, but the end results are good. These are also on the pricey side. Best to have alignment checked afterwards.

Coil-overs have been around awhile, but not too many are seen in trucks as are "car" hot rods. These are a great replacement for the original spring and shock. Plus, the coil-overs have a built-in adjustment for ride height, so if you want to give itan extra drop, you can use the special wrench and it's done. These are very pricey, but very nice as they are usually chrome/aluminum and polished for show. Not available for all types, but more kits are coming out, GM kits are already available.

Air bags are becoming the end-all greatness of lowering. After some removal of old parts and bolt-on work of new bags, you can have a fully adjustable ride at the flick of a switch. Very expensive. Sometimes requires fabrication of bracketry or other parts. Many kits are already available.

Hydraulics have been around along time, usually in the old-school lowrider crowd. However, hydraulics are the most versatile suspension you can get. Kits can actually be had for less than an air bag setup, but other costs (batteries, solenoids, etc) keep it about the same. Hydraulics take alot of work to setup and most of the time, the front shock (if mounted inside the spring originally) has to be moved to another location and the stock upper shock hole has to be enlarged for the hydraulic cylinder. Most people think that hydraulics are messy and that ride quality has to suffer. This is very untrue. It does require space for batteries and such, however, air bag setup have to have room for tanks, so they equal out. If you want maximum playability, hydraulics are just for you. You can hop, drop, lean, and even 3 wheel with a hydraulic setup.


Rear Lowering

The rear end has several options for lowering as well, again some of these methods can be combined:
1. Shortening coils (coil rear suspension)
2. Coil-over conversion (coil rear suspension)
3. Lowering blocks (leaf spring suspension)
4. Lowering shackles (leaf spring)
5. Flip kits (leaf spring)
6. lowered "de-arched" springs (leaf)
7. Aig bags
8. Hydraulics

Shortening the coils on a coil rear suspension works about the same as front suspensions, except you don't have to worry about the steering components or alignment.

Coil-overs can be use in the rear as a replacement to original coil springs. Usually these are used when completly replaceing the rear suspension, ie ladder bars, 4-link.

Lowering blocks are placed bewteen the leaf spring assembly and the axle-mounting plate. Simple bolt-on operation. If lowering alot, you might need some shims to correct your pinion angle. These work only if your axle is already on top of the leaf spring assembly.

Lowering shackles replace the originals. Might require some extra work if your oringinals are riveted on.

Flip kits are used when your axle is under the leaf spring assembly. This kit brings the axle above the assembly. Rquires that the leaf springs be removed to accomplish this task.

New leaf springs can be bought to lower the ride as well. These usually come in the form of a monoleaf spring that effectively lowers the rear. Can be pricey.

Airbags are great for coil rear suspensions. replace the springs are you're good to go. On leaf suspensions, not as easy. Usually need to have it lowered at min ride height, then have bags to raise it up.

Hydraulics are about the same. Cuts have o be made for the cylinder, this is usually a cut in the bed of the truck. Not always a desire for people to do. On leaf springs, a "coil-over" method can be employed and can be used as accompanying piece as the airbags are to the leafs. Again, both hydros and bags are more expensive.

Also a good idea to get shorter shocks for the rear as well when done. I hope some of you can use this info. I figured it would be a good intro for some who are new. Good luck!!


Last edited by CustomChevy; 04-06-2003 at 04:41 PM.
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