OME 2" lift with heavy duty springs rides harsh

gg1

TJ Enthusiast
I am thinking about trading out my HD springs for regular ones. 2" life from OME. My Rubi is stock other than the lift, so I don't think I need HD springs. Anyone know the difference? Ride height the same? I am running 33's, but there is plenty of clearance for my Jeep considering it is babied. lol

Any help would be great. Also the cheapest place to get the springs? I will probably want new and sell my HD's.

Thanks.
 

JMT

The Jeep Guy
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Feb 27, 2017
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Texas Hill Country
I am thinking about trading out my HD springs for regular ones. 2" life from OME. My Rubi is stock other than the lift, so I don't think I need HD springs. Anyone know the difference? Ride height the same? I am running 33's, but there is plenty of clearance for my Jeep considering it is babied. lol

Any help would be great. Also the cheapest place to get the springs? I will probably want new and sell my HD's.

Thanks.
Changing springs won’t improve your ride. As @cliffish said, what shocks and tire pressure are you running? Those are the top two factors that affect ride quality.
 
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gg1

gg1

TJ Enthusiast
25 pounds of tire pressure and OME shocks that came with the kit. Why wouldn't the HD springs be stiffer than standard? One would think the HD springs would be less forgiving?
 

JMT

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I am thinking about trading out my HD springs for regular ones. 2" life from OME. My Rubi is stock other than the lift, so I don't think I need HD springs. Anyone know the difference? Ride height the same? I am running 33's, but there is plenty of clearance for my Jeep considering it is babied. lol

Any help would be great. Also the cheapest place to get the springs? I will probably want new and sell my HD's.

Thanks.
Changing springs won’t improve your ride. As @cliffish said, what shocks and tire pressure are you running? Those are the top two factors that affect ride quality.
 

JMT

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Feb 27, 2017
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25 pounds of tire pressure and OME shocks that came with the kit. Why wouldn't the HD springs be stiffer than standard? One would think the HD springs would be less forgiving?
If you just rode down the road with springs the rig would just bounce, bounce, bounce. The shocks valving determines how to return the spring to ride height. It can be abrupt, it can be slow, it all depends on the valving. I’ve read that the old OME Nitrochargers rode better than the current one’s. Many people on here swear by the RAncho 5000X. If you tried anything, I’d try changing shocks.
 

Jerry Bransford

TJ Guru
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Nov 9, 2015
10,276
Escondido California
25 psi is entirely appropriate for a 33x12.5 load range C tire supporting a vehicle with the weight of a Wrangler. The current OME Nitrocharger Sport is notorious for being significantly stiffer riding than their previous Nitrocharger. My recommendation is to replace the shocks with the Rancho RS5000X which will give a significantly better ride. My previous RS5000X shocks gave both a great street ride and superb offroad control.

Your stiff ride is definitely not being caused by the springs. They're not what give a good or bad ride.
 
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TurboTJ

TJ Enthusiast
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Jan 5, 2019
135
Walnut Creek, CA
Basic physics says that stiffer springs will result in a rougher ride. The shocks may be the contolling factor but the equation F=MA (where M is the mass of the sprung weight) says that greater spring constants (pounds per inch or whatever) will result in greater acceleration of the sprung mass. I went from the OME HD springs to the non-HD springs and the ride was much better. Of course my lift went almost to zero with the non-HD springs.
 

JMT

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Basic physics says that stiffer springs will result in a rougher ride. The shocks may be the contolling factor but the equation F=MA (where M is the mass of the sprung weight) says that greater spring constants (pounds per inch or whatever) will result in greater acceleration of the sprung mass. I went from the OME HD springs to the non-HD springs and the ride was much better. Of course my lift went almost to zero with the non-HD springs.
This will probably just turn into an argument, but the HD springs are 160 in/lbs and the LD are 140 in/lbs. Not enough difference to make a noticeable ride difference. Sometimes we make a mod and our minds tell us it is better than it really is, like we deceive ourselves to justify the change we made and the $$$ we spent.
 

TurboTJ

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Jan 5, 2019
135
Walnut Creek, CA
I can only speak from direct personal experience. The non-HD springs (same OME shocks) rode noticeably better than the HD springs. I changed to the non-HD because the ride was so harsh.
 

Jerry Bransford

TJ Guru
Supporting Member
Nov 9, 2015
10,276
Escondido California
Basic physics says that stiffer springs will result in a rougher ride. The shocks may be the contolling factor but the equation F=MA (where M is the mass of the sprung weight) says that greater spring constants (pounds per inch or whatever) will result in greater acceleration of the sprung mass. I went from the OME HD springs to the non-HD springs and the ride was much better. Of course my lift went almost to zero with the non-HD springs.
You're being confused by the correct application of "basic physics" here. The spring rate is all about how much the spring will deflect with a given amount of weight.

Springs are only there to support the weight of the Jeep. A higher spring rate will position the Jeep higher and visa-versa. Using a spring with a much higher rate than needed will contribute to a stiff ride, and using one with a rate that is lower than needed will result in the spring being partially compressed at ride height. The latter will reduce ride height. But springs designed for a Wrangler will be very close in spring rate and won't ride appreciably differently. What then will have the most direct effect on ride quality? The shock absorber.

So when the appropriate rate spring is installed to give the correct ride height, the quality of the ride is mostly under control of the shock absorbers and the balance by the tire's load range and its air pressure.

If you want improve your ride, install a better riding shock. Again, your OME Nitrocharger Sport shocks are well known for having a very stiff ride, significantly stiffer than the Nitrocharger predecessor.

But you can ignore this line of advice and go with a lower rate spring. You'll end up with a lower ride height, existing shocks too tall for the reduced ride height, and the same ride as before.
 
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glwood

Jeep # 13
Supporting Member
Sep 16, 2016
5,835
Albuquerque, NM
I am thinking about trading out my HD springs for regular ones. 2" life from OME. My Rubi is stock other than the lift, so I don't think I need HD springs. Anyone know the difference? Ride height the same? I am running 33's, but there is plenty of clearance for my Jeep considering it is babied. lol

Any help would be great. Also the cheapest place to get the springs? I will probably want new and sell my HD's.

Thanks.
If you were closer, I'd trade you, just as an experiment to try the HD. I'm happy with the LD, but I wouldn't mind the switch.
 

JMT

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If you were closer, I'd trade you, just as an experiment to try the HD. I'm happy with the LD, but I wouldn't mind the switch.
Just make the trade by shipping. Won’t be more than $25 or so. I want to watch this.
 

bobthetj03

vibrajeep
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Feb 3, 2017
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ARB designed the 2nd gen sport shocks to pair well with the heavy pig JKU's IMO. You really can't blame them. It's the natural progression of what sells. Sell the OME shocks and get one valved more specific to our lighter T's. I have the HD springs. Have had them for years. My tj is light. I wore out my first gen OME nitros and went with Ranchos RS5000X. These shocks duplicated the ride qualities of my previous shocks, and at half the price.
 
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TurboTJ

TJ Enthusiast
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Jan 5, 2019
135
Walnut Creek, CA
I’ve done a bit of research on this. I believe the front LD springs are the 2932 and the HD springs are the 2933. The only difference between these is the unloaded height which is 470-480 mm for the 2932 and 485-495 mm for the 2933. The spring rates, bar diameter and number of turns are the same. The rear LD springs are the 2941 which have 15 mm bar diameter, 375-390 mm height and 140 lbs/in rate. The HD springs are the 2942 which have 15.5 mm bar diameter, 360-380 mm height and 160 lbs/in rate. Note that the rear HD springs are actually shorter than the LD springs although the rate is higher. What to make of this? I am not sure, just reporting what I have found.
 
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JMT

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I’ve done a bit of research on this. I believe the front LD springs are the 2932 and the HD springs are the 2933. The only difference between these is the unloaded height which is 470-480 mm for the 2932 and 485-495 mm for the 2933. The spring rates, bar diameter and number of turns are the same. The rear LD springs are the 2941 which have 15 mm bar diameter, 375-390 mm height and 140 lbs/in rate. The HD springs are the 2942 which have 15.5 mm bar diameter, 360-380 mm height and 160 lbs/in rate. Note that the rear HD springs are actually shorter than the LD springs although the rate is higher. What to make of this? I am not sure, just reporting what I have found.
Right. The different heights, for example with the 2941 LD springs, 375 and 390mm, are the heights of springs A and B, they are side specific.

The fact the HD’s are longer but with a higher spring rate just means that they will give a certain ride height given a specific sprung weight. Most people that get the HD’s and run light (e.g. no back seat, no hardtop) complain that they have too much rake.

Generally, you want the longest spring you can get that will give you your desired ride height.