Coil spring part numbers

[KurtP]

yep i agree.

for example. The payload on my mojave is 1,100 or 1,200 pounds. Pretty low. And i have the widest axles the most reinforced fram reinforced steering components stiffer front springs....but... softest rear springs.

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[basicGlad]

Seems like I may need to take out my springs (443AC & 444AC) and measure if they have unequal distance between each coil (are progressive)

 

[ShadowsPapa]

Seems like I may need to take out my springs (443AC & 444AC) and measure if they have unequal distance between each coil (are progressive)

No don't go by that! My original Overland rears had varying spacing - uppers closer.
That's not a great "tell" on springs these days.
The max tow rears I used had varying WIRE DIAMETER. Further, modern springs can have varying rates just in how the steel is treated.

Here's my original Overland rear springs - and look at the closer coils on the end at the top of the photo -

Now here are Rubicon springs - note the closer spacing at one end, and the fatter wire at the other end -

Now here are max tow rears -

Gee, they all have a certain varied spacing between the coils - and look at the Rubicon spring wire, fat at one end less fat at the other.

Could you have told by looking if I hadn't said which was which - which springs came from what level JT?

 

[ShadowsPapa]

yep i agree.

for example. The payload on my mojave is 1,100 or 1,200 pounds. Pretty low. And i have the widest axles the most reinforced fram reinforced steering components stiffer front springs....but... softest rear springs.

Now THAT's ironic! A truck made to take a heavy pounding in sand and fast over rough ground, but has a lower payload. Beefed up frame and the axles that could easily handle such a load.
Perhaps that truck itself is heavy?
What's the curb weight as compared to curb weight of the others? I've not looked.........
Overland has a lower payload IN PART because it's heavier than Sport - well, usually, if loaded with options. But then, the Overland options don't weigh much as they are mostly electric or electronic. The axles are lighter because they are less wide, but can't be a lot.

 

[KurtP]

Now THAT's ironic! A truck made to take a heavy pounding in sand and fast over rough ground, but has a lower payload. Beefed up frame and the axles that could easily handle such a load.
Perhaps that truck itself is heavy?
What's the curb weight as compared to curb weight of the others? I've not looked.........
Overland has a lower payload IN PART because it's heavier than Sport - well, usually, if loaded with options. But then, the Overland options don't weigh much as they are mostly electric or electronic. The axles are lighter because they are less wide, but can't be a lot.

Slightly heavier than a Rubicon. The rear springs are in between a rubicon rear spring and a sport with trailer tow, which reduces the Mojave GVWR by 90lb of a Rubicon and reduces payload to 1115 from 1250. Also reduces towing from 7000 to 6000. The only difference between a Rubicon and Mojave from a gvwr perspective is the spring rate of the rear spring.

 

[ShadowsPapa]

Slightly heavier than a Rubicon. The rear springs are in between a rubicon rear spring and a sport with trailer tow, which reduces the Mojave GVWR by 90lb of a Rubicon and reduces payload to 1115 from 1250. Also reduces towing from 7000 to 6000. The only difference between a Rubicon and Mojave from a gvwr perspective is the spring rate of the rear spring.

OK, makes sense. I would have "assumed" the Mojave to be a bit heavier due to the other reinforcements, the shocks with remote reservoirs, and that sort of thing.
So in essence, the Mojave payload and towing are about the same as the Overland.
Perhaps you saw I put Rubicon front springs under my front and Sport S max tow springs under the rear. Oddly, the max tow springs were SHORTER than the Overland springs and dropped the rear by about 3/8". I didn't really want that, I only wanted it to not sag as bad with 500 pounds of trailer tongue or playload in the box. It drooped badly before. I have not really tried any real load or my trailer since the spring swap.

 

[KurtP]

OK, makes sense. I would have "assumed" the Mojave to be a bit heavier due to the other reinforcements, the shocks with remote reservoirs, and that sort of thing.
So in essence, the Mojave payload and towing are about the same as the Overland.
Perhaps you saw I put Rubicon front springs under my front and Sport S max tow springs under the rear. Oddly, the max tow springs were SHORTER than the Overland springs and dropped the rear by about 3/8". I didn't really want that, I only wanted it to not sag as bad with 500 pounds of trailer tongue or playload in the box. It drooped badly before. I have not really tried any real load or my trailer since the spring swap.

more or less yeah. Height and rate can be independent of one another. Iirc the overland gvwr is 5800. Its 6140 on mojave. So i mis quoted above. Mojave is ~110 lb lower gvwr and ~140 reduced payload From rubicon. Axle load remains the same.

 

[ShadowsPapa]

more or less yeah. Height and rate can be independent of one another. Iirc the overland gvwr is 5800. Its 6140 on mojave. So i mis quoted above. Mojave is ~110 lb lower gvwr and ~140 reduced payload From rubicon. Axle load remains the same.

Yes, 5800/Overland

 

[KurtP]

https://www.truckcamperadventure.com/raising-your-trucks-payload/

https://itstillruns.com/increase-trucks-gvwr-7303951.html

they dont address brakes or wheels however, which can be a weak link sometimes. Also, check the laws of various states. Some states, like Florida and California as two examples, weight axle load rating as primary to GVWR rating. So, as an individual user, you can exceed GVWR as long as you don't exceed axle rating or trip the requirement for a CDL license. Some states like Washington add GVWR automatically to your registration, and authorize you as a user to "pay up" for additional GVWR and a different vehicle inspection.

In short, GVWR isn't necessarily a hard and fast rule the way axle rating is. I have found, generally, that if you are within your axle rating and tire load rating and dont look like a jingle truck, youre fine....and some states even allow you to up-rate your GVWR on your legal registration based on that axle rating.

You also need to check with your insurance company's UNDERWRITERS to determine if they are concerned with GVWR or axle and tire rating. USAA, State Farm, Travelers, and I think All State have previously gone by Axle rating superceding GVWR, but you need to check.

my opinion: If you are going to go over GVWR, understand this: 1- if you are over that door sticker, you *COULD* have a problem depending on who has you for what. if you are within your registered GVWR and axle rating, it would be very difficult for a citation to "stick", and chances of getting one in the first place are really low. 2- the best way to go about doing it is know EXACTLY what your weight will be, and ensuring you are within your axle and tire load ratings, and that your spring has sufficient resistance to carry that load from the formula above. 3- tag your vehicle in your state with a GVWR rating that matches what you need. 4- ensure your insurance policy accommodates that GVWR. Sending your insurance company a copy of your new registration would likely count as "notification" to the company of what your GVWR is going down the road.

 

[basicGlad]

Thanks for the info @KurtP
Stopping distance is always a factor I pay attention to. I'm not trying to increase my payload. I just want to make sure putting on the Rubicon springs won't kill my payload // take away from my 1650lbs of payload. I put 900-1000lbs in the bed and 4 people in the cab.

After reading those two articles most important part seems like springs should bottom out first before anything else fails. <That, plus my real payload limit is resting on my non wide trac Dana 44s more than the springs.

Question: rubicon springs are higher but have more sag? I dont understand why rubicon springs feel softer, floaty or have a squishy feeling. Im trying to think through rubicon is a heavier truck with a softer spring and more equiptment but same payload (payload on door sticker is just reduced from extra equiptment)?

 

[ShadowsPapa]

Thanks for the info @KurtP
Stopping distance is always a factor I pay attention to. I'm not trying to increase my payload. I just want to make sure putting on the Rubicon springs won't kill my payload // take away from my 1650lbs of payload. I put 900-1000lbs in the bed and 4 people in the cab.

After reading those two articles most important part seems like springs should bottom out first before anything else fails. <That, plus my real payload limit is resting on my non wide trac Dana 44s more than the springs.

Question: rubicon springs are higher but have more sag? I dont understand why rubicon springs feel softer, floaty or have a squishy feeling. Im trying to think through rubicon is a heavier truck with a softer spring and more equiptment but same payload (payload on door sticker is just reduced from extra equiptment)?

Rubicon people should WANT their springs to collapse when they get into really uneven ground - over rocks and such. If the spring is stiff, the vehicle can't flex to walk over things. The key with the solid axle with sway bar disconnect is to let that puppy flex all it wants - shove that high end wheel clean up into the fender well while the other drops to the limit of the shock. If the spring resists you at all, it's not going to play nice on extreme ground.
The purpose of a Rubicon isn't to haul a big load - it's to go where no man - or woman - has gone before and do it nimbly.

Yes, options and extra factory weight DO reduce payload if comparing like-to-like vehicles. A base Overland would have a higher payload than I do - but not by much as the options for the Overland are LIGHT - mostly electric and electronic - gadgets, etc. So it's not just vehicle weight, either but that does play into it. A BASE Rubicon will have better payload than one ordered factory with the optional steel bumper, steel skid plate and other fun stuff because you have a big amount of extra weight. I think the bumper and skid plate alone could add 80 pounds or so - my steel bumper is about 80, then the steel skid plate is WAAAY heavier than that plastic air dam thing I took off. I could hold the air dam with metal backer out in one hand with my arm extended it's so light.

I think you are getting the gist of it.
Like me - you just don't want to load it with your sticker payload and look like you are 'coon hunting in the trees or something with your headlights sending a signal to Batman.

 

[KurtP]

Thanks for the info @KurtP
Stopping distance is always a factor I pay attention to. I'm not trying to increase my payload. I just want to make sure putting on the Rubicon springs won't kill my payload // take away from my 1650lbs of payload. I put 900-1000lbs in the bed and 4 people in the cab.

After reading those two articles most important part seems like springs should bottom out first before anything else fails. <That, plus my real payload limit is resting on my non wide trac Dana 44s more than the springs.

Question: rubicon springs are higher but have more sag? I dont understand why rubicon springs feel softer, floaty or have a squishy feeling. Im trying to think through rubicon is a heavier truck with a softer spring and more equiptment but same payload (payload on door sticker is just reduced from extra equiptment)?

spring height, spring sag, spring rate are not 1:1 related. You can have a tall spring that will compress more than a shorter spring; but still have higher ride height while compressing more under load.

i dont know what all the spring rates of the various springs to advise you. My recommendation would be simply go aftermarket if you want a stiffer lift spring, or do a spacer lift That lifts the truck without altering your spring.

Also dont forget that how harsh or plush a truck rides has more to do with damper tuning than it does outright spring rate. (Up to a point)You can have a relatively stiff spring with a soft damper that can feel more bump compliant than a soft spring with a firm damper.

my guess based purely on experience but no real data is that the rubicon has extremely soft dampers and at a minimum soft front springs. I base that on how badly they drive on the road. Personally, i wouldnt put rubicon springs on my truck. If youre happy with the way your truck drives, hauls, and handles but just want more lift and control, then a spacer lift with better shocks is likely your best route.

 

[ShadowsPapa]

Good point on spring rate, height, etc. - I put max tow springs under my truck - they don't sag as much but are shorter by a good half inch and yet didn't drop the rear that much.

I'm going to toss out a speculation here that Rubicon shocks have a faster compression rate than expansion rate, opposite what drag racing shocks have. Racing shocks expand fast and compress slowly. That way the front end comes up fast for weight transfer and settles slowly to keep that transfer to the back for a longer period than standard shocks would do.

I would think that you'd want a Rubicon axle to go up rather easily and not resist compression so much.
That's my opinion, anyway.

I put on Rubicon front springs and shocks all around. You have more road feel, I gained height up front but the ride is still quite nice. When I put the heavy bumper, winch and skid plate up front it only settled .5" with the weight but still rides ok.

Next step - .75" spacer all around because the max tow springs dropped the back a tad.

 

[Diggs9]

is there a thread telling what the free length of the springs?
has anyone seen those numbers ?

 

[SquirrelNuts]

Another update. Swapped the rear Rubicon Springs for the Max Tow springs over the weekend. Nothing changed on the front. I can notice a difference in the ride quality with the max tow springs back in the rear. The "Floaty" feel is gone. When I compared both springs side by side I could not visually see a difference. My guess is the max tow springs just have a stiffer spring weight over the Rubicon springs. How that translates offroad I won't know until we are allowed out of the house again, but seeing as though I plan on adding some things to the bed I'll probably stick with the max tow springs for now. Eventually.

Have you settled on an optimum spring/spacer/shock combo for your JT?

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