Hey everyone, I know There are a lot of brands making progressive rate front coils and was wondering who makes rear progressive rate coils. I thought ROCKKRAWLER were progressive front and rear but I guess it's just the front. I know synergy has them but I don't want to get them by default if you know what I mean.

 

The RK springs are not?!?! I was under the impression that dual rate was probably the most accurate term for their springs, but damn! They were going to be my choice. :-(
Other brands to check on: AEV, Old Man Emu, and/or Off Road Evolution Plush Ride Coils.
Damn, you caught me off gaurd with this one!

 

ROCKKRAWLER has front dual rate/progressive rate coils but not rears. My search continues

 

Check out metalcloak....just ordered them I was in the same boat...their stuff is amazing.amazing

 

Metal cloak are dual rate. Evo, Teraflex and OME is single rate. AEV and Poly Performance make progressive rate. Maybe some others out there are progressive.

 

What's the difference between dual & progressive rate?

 

Can anybody chime in? I think they are the sane thing but that's just a guess

 

Here is the little that I know. If this needs to be refined I hope someone will correct me.

Single rate coils use a similar metal, coil diameter, and distance between coils to create a spring that has uniform resistance throughout range of motion. Great for predictability.

Dual rate coils use zones. Maybe the last several inches of the coil use a alloy with more flex, the diameter of the coil itself is smaller or the distance between coils has been altered in a way that a zone of the coil will compress more easily. Like a soft or springy zone on the ends of the spring with a more rigid center. The soft areas eat up little bumps while the rigid center is there to handle the big stuff.

True progessive rate coils use varying alloys, coil densities, and/or distances between springs to have a spring that behaves diferntly depending on area, but the changes are throughout the spring, not in specific zones. My understanding is that these are very difficult to make well.

 

Synergy Suspension coils are progressive front and rear..
and of course AEV too..

I just picked up some Synergy Springs

 

"Everything works in theory."