shelby5041

hi

my jeep cherokee 1997 is sagging bad....the rear leaf springs are m shaped instead of u shaped

they need to be replaced

i do not offroad at all striclty normal driving but i do use it to carry weight in the back such as tools and oither heavy items

i would like a heavy duty leaf spring not standard duty

they have crown and dorman brands for my vehcile

it seems the crown is a 7 inch arch vs 5.5 inch arch on dorman

the crown is considered heavy duty vbut not sure about the dorman

i would like to know which i would be better off buying....for durability and lasting a long time

i can get dormans with bushings already in them for 104.00 free ship
crown is 79.10 without bushings bushings are about 15.00 a set


any input would be great....i dont want to make a bad decision

thank you

studmuffin

I have heard that the dorman are equivalent to the upcountry package leafs meaning they are heavy duty. I am running dorman leafs with aal and they are holding up pretty well. I bought the leafs and the aal new so there was no prior sag.

shelby5041

hi facts are the dormans are only 5.5 inch arc and the crowns are 7 inch arc


so not sure how people can say the dormans are heavy duty'


they are not heavy duty they are standard duty direct replacement for stock

shelby5041

the larger the arc measurement dictates heavy duty or not

toasterknight

Arc height has nothing to do with HD or not it's is the spring rate that matters. A heavy spring will have a shorter arc as it will sag less where a soft spring may sag a lot.

shelby5041

hi i disagree with that but thats ok....the larger the arc dimension means its got more u shape to it and that means its stronger....common physics means its stronger but thats assuming both sets of springs use same dimensional and type of steel....

anyways the crowns are rates standard duty 5.5 arc medium duty 6.5 arc and heavy duty 7.0 arc

so is crown wrong?

shelby5041

stronger to me would mean less sag over time

and the larger arc means less sag assuming both springs use similar steel

shelby5041

and yes 100% the spring rate matters but im assuming spring rate is same .on both and if they arent they need to give that information or something so we can comparre......and the only diff is arc dimension

i was just disagreeing with the arc length mattering...it does matter

shelby5041

ok how about this

whats is the load capacity per spring on the dormans 929-301 vs crown
4886186AA

that should tell us which one is heavier duty correct?

studmuffin

They have the same spring rate and both advertise being heavy duty. Dorman come with bushings and crown do not. Keep that in mind since bushings aren't cheap and a pita to istall. It's apples and oranges here and just like the other guys said arch has nothing to do with spring rate it just adds a bit more height more than stock but hardly noticeable. Personally though if I was building a tow rig I would go with a small lift rubicon express springs.

studmuffin

With that being said the crown springs are equivalent to the upcountry package as they have a bit more arch hence a bit more lift however spring rate is the same you are getting the same quality steel.

BlueRidgeMark

That is the important question. How heavy is the steel?

It's possible to have a light spring with more arc than a heavy spring.

Shooting Brake

Well...been where you are...serious sag..Yep..spring droop.I did some checking and went with the quick easy way out...Monroe 58594 coil overs...Amazon reviews were great for the droop...and ride.I put them on...coils took some of the load and springs sit normal again..actually she sits higher than stock....Smoothed out the ride.. that was unexpected...Stance was higher and I will enjoy them as long as they last....spring set can wait till my wallet catches up.

toasterknight

Your going to have nice holes in your floor pan. Fix the problem correctly with new springs rather than a bandaid.

BlueRidgeMark

Yep. Shocks are not made to take the weight of the car, they are made to dampen oscillations. Take a look carefully at the shock mounts. They are not solid structural members. They are not made to take the weight of the car.

Shock makers sell what suckers will buy - that's why you see coils and air type shocks. They are bad news.