So everyone is always talking about progressive coils that come with the AEV lifts.
What's the difference between them and other coils?

 

The stock coils are a progressive design. The idea behind a progressive spring is to allow for a relatively plush ride while at the same time if the vehicle is heavily loaded the springs are able to operate without being overly compressed. The springs get progressively stiffer as the load is increased.

The other design, which is more frequently used (for a number of reasons including ease of design), is a straight rate spring. A straight rate compresses at a linear rate.

What it boils down to is that each is a compromise with the progressive being biased to on-road everyday use, and the straight rate being biased to off-road/flex.

Both designs can and will work in on or off road conditions.

 

Progressive rate springs suck. Regular rate springs don't suck. ...and I don't think the stock springs are progressive. If they were, there wouldn't be over 20 different part numbers, because they could handle different weight ratings.

 

Why do progressive suck?

 

Nearly every word of this is dead wrong.

 

I might be wrong about the stockers being progressive, but I'm not wrong about progressive coils sucking. That's my opinion. It's mine and it's not wrong. Can you give us some proof that the stock coils are progressive? This is the first I've ever heard of it.

 

I'm just sitting here waiting eagerly for a nice debate to start

 

Progerssive coils almost always have a few coils that are either extremely close together, or actually touch. To "ME", there's no purpose in that. It's a wast of spring wire. If they are touching at static ride height, how can that section be beneficial in supporting weight other than basically acting like solid a spring spacer? Pretty much the same if they are extremely close. The idea behind progressive springs is that they store energy that's released as the vehicle is loaded. In other words, they are a variable rate spring. I've never really bought the concept, because I've seen many vehicles where they just seemed not to work and actually did just the opposite. They sagged when loaded. That's NOT what progressive springs advertise. As for the JK having progressive springs from the factory, I just got off the phone with my friend who works in the body shop parts department at the local Dodge dealer in Macon, and he says best he can tell, they are not, because each number list a distinctly different rate and it says nothing about being variable or progressive in the parts book.

 

No debate. I'm curious too. They may BE progressive from the factory. I could well be wrong. But so far, I've found no evidence to support it. There's no debating my opinion of progressive rate springs because I don't like them. That cannot be argued with. LOL

 

Just look at it. The coils wind gets progressively tighter.