[Steamer98]

I understood the CS034RA part # replaced the JC1A # packs which are considered the Medium load packs? These would give the most lift they offer, outside the AAL.

[Steamer98]

Quote from Dirk at DPG
From this thread http://www.jeepforum.com/forum/f11/not-happy-old-man-emu-lift-249046/index10.html?highlight=happy

"That's a broader question than I wanna post to completely, but here's the down low:
JC1A is now CS034RA
This leaf typically nets close to 3" of lift on a stock XJ.

JC1B is now CS034RB-
This pack is closer to 2" of lift.
We should keep in mind that advertised lift heights do vary a bit. This is true throughout the industry. For example, RE kits usually sit taller than advertised on a stock jeep.
You could put the exact same kit on 3 different jeeps and net 3 different lift heights, due to how each jeep is set up. Another little know fact is that XJ's came with a number of different leaf spring packs over the years. Lift heights and spring rates were not all identical.

There has been some confusion here because ARB has referred to the JC1B as a medium leaf and the JC1A as a HD leaf pack. They both have the same # of leafs, and the leafs are the same thickness. Therefore, with these leafs, the spring rates are basically the same. The reason the JC1A sat a bit taller was simply because they are arched more. To me, that's not HD. HD would mean a higher spring RATE to me. I've had a lot of people call to order OME leafs, and they said they didn't know if they wanted to JC1A or the B, but whichever one was "heavy duty"... Of course, the taller spring would hold more weight at a certain height than the other.

The JC2A and JC2B were the leafs with the straight overload leaf. They were designed for towing and hauling heavy loads. Obviously, the new OME Dakar part#'s are the CS035** series. I usually don't recommend these leafs, so I'm not sure which part#'s correspond to 2" or 3". I don't even have the new part #'s for those leafs listed in my OME books.

OME has also had a #JCXL extra leaf available for their packs. That new part# is
D22XL. These are not the typical aftermarket AAL, which is usually fatter and much more heavily arched than the springs they fit with. While the typical AAL FORCES the flatter pack to arch, creating a conflict within the pack, the OME extra leafs are the same thickness and arch as the OME pack. This is actually a compliment to the pack. These leafs usually add about an inch of lift and a bit of extra spring rate too. They still make for a nice riding pack that flexes well too.

We've built a bunch of different suspension set-ups with a variety of these and other parts for lifts netting anywhere from 2" to 4.5" or so. Applications vary greatly depending on each jeep, how heavy it is, how that weight is distributed, (front & rear) the lift height and ride characteristics desired, and so on.
That's not something that can easily be summed up here- especially considering that every jeep is different. Hopefully, that helps a bit though."

[gorman]

Steamer98, you are 100% correct with everything in that post. One thing that Dirk from DPG does differently thought it to use two CS034RA spring packs together to get 3" and this I guess would net 3". How mine is setup however is with a CS034RA on the driver's side and a CS034RB on the passenger side - the higher arch of the RA spring was supposedly created to compensate for the constant weight of the driver rather than increased lift.

Also the OME catalogue list a light load and medium load spring, rather than a medium and heavy duty, but I guess it is just terminology that differs rather than actual parts.

I attach three pics scanned from the OME calalogue. This first shows the OME options available for an XJ. In the descriptions at the bottom you can see that two A springs can be used where max trimming is required.


In the second pic below I've listed the specs of the rear leafs - this shows that the free height of the A spring is exactly 25mm (1") from the B spring.


The last pic is scanned from the guideline section - here they explain what is meant with "light load" and "medium load" and also when and where the A and B springs are usually used.

[Steamer98]

Very good info Gorman!
Seems to be alot of questions on the OME setups lately, that info should be sticky'ed