Front Leafs...HD vs Standard?

skiznits

New Member
Joined
Jun 2, 2022
Messages
10
Location
CA
Ok, Sold my audi and just dusted off the 4.0L 91 YJ which I now really enjoy driving but it needs some work. The radiator and brakes had major issues so repaired those items to get it back on the road.

Ride is not great. I want to replace springs and the shocks. Springs are original issue and I dont want to lift it bc I bet the driveline is set in its ways being 30 yrs old.

Only extras on this are: a hardtop, steel cargo rack, aftermarket rear bumper.

Not many options for OEM(?) leaf replacements but the ones that come up are:
Crown
Dayton

Looks like there is only one rear pack for both brands which is fine and makes my decision for that simple.


BUT the front has a heavy duty(HD) and a regular duty.
CROWN Spring rate for the HD is 272 lb/in
CROWN Spring rate for the Regular 139 lb/in

DAYTON doesnt list spring rate but mentions 'Load rating' whatever that is.
HD 840
Regular duty 650

Does anyone have and experience with these options. Is the regular duty for the 4.0 or the 2.5L or does it matter. Want to keep it level as possible to run 30's which it currently has on it. HD front springs may keep the front end high?


I used quadratec and rockauto to source this info above. YJ rock auto link. There are a few other brands but I think I listed the most common.

Skiz
In OC California if there are any locals reading
 
OP
skiznits

skiznits

New Member
Joined
Jun 2, 2022
Messages
10
Location
CA
HD will not sag as much and will give a stiffer ride. That will be the difference.
I visualize the HD to be used with a winch, aftermarket bumper etc. Too bad theres no good real time use info out there...

But looking into the dayton springs the HD is actually with a lower free arch than the regular by about an inch suggesting the increased stiffness like you mention.

I just cant help but think that without additional weight, HD will still be higher than expected.
 
OP
skiznits

skiznits

New Member
Joined
Jun 2, 2022
Messages
10
Location
CA
Ok, Sold my audi and just dusted off the 4.0L 91 YJ which I now really enjoy driving but it needs some work. The radiator and brakes had major issues so repaired those items to get it back on the road.

Ride is not great. I want to replace springs and the shocks. Springs are original issue and I dont want to lift it bc I bet the driveline is set in its ways being 30 yrs old.

Only extras on this are: a hardtop, steel cargo rack, aftermarket rear bumper.

Not many options for OEM(?) leaf replacements but the ones that come up are:
Crown
Dayton

Looks like there is only one rear pack for both brands which is fine and makes my decision for that simple.


BUT the front has a heavy duty(HD) and a regular duty.
CROWN Spring rate for the HD is 272 lb/in
CROWN Spring rate for the Regular 139 lb/in

DAYTON doesnt list spring rate but mentions 'Load rating' whatever that is.
HD 840
Regular duty 650

Does anyone have and experience with these options. Is the regular duty for the 4.0 or the 2.5L or does it matter. Want to keep it level as possible to run 30's which it currently has on it. HD front springs may keep the front end high?


I used quadratec and rockauto to source this info above. YJ rock auto link. There are a few other brands but I think I listed the most common.

Skiz
In OC California if there are any locals reading
Anyone know if there were different springs for the 2.5L vs the 4.0? I dont think they had upcountry type stuff back then.

I know Im digging deep here...sorry this info will be difficult to find. That info is pre online forum stuff hahaha