Spring replacement, leveling springs

[Glider]

Got the fronts installed a last week. I wasn't there for the front install but they said they couldn't the front in full length and cut 1 coil off same as we did on the rear. I haven't measured it to see actual lift and haven't driven it much. I plan to use a fair amount this week and will post results.

JRT are there any other options I need to know on the 5125? You said they were too light. Can you elaborate? I'm basically a mall crawler but do go offroading. It's mainly slow cruising and slow flexy offroading. No mid/high speed offroad stuff.

Bilstein 5125 Offroad Shocks - ShockWarehouse

The 5125 Series offers Bilstein technology for custom applications. 5125 Series shocks feature Bilstein's superior single tube high gas pressure design for the up most in consistent fade-free performance and long life. Bilstein's patented Deflective self-adjusting valving delivers improved...

www.shockwarehouse.com

 

[TOBASH]

Another way to level your vehicle is to calculate how much difference there is between what you want and what you currently have. Then you use simultaneous equations to calculate how much of the unsprung spring height needs to be cut. Older saggy springs on these vehicles give less of a rough ride, and in someways saving your springs by cutting them to size will improve drive ability.

In order to do your simultaneous equations you need to measure the taller spring when compressed and then measure the spring when unsprung. You can calculate how much of the spring when compressed needs to be cut and re-calculate what that means in the unsprung spring. Then you need to cut 2 inches shy from that mark and use a blow torch at exactly the mark in order to bend the spring so that it sits properly in the perch . After using the blow torch I would re-quench the spring in oil. Then re-insert the spring and measure to ensure you got what you wanted.

This is the old-school way of dealing with coil springs to lower vehicles properly.

 

[Glider]

It's odd you say that. I was thinking that after the springs settle the rear will most likely be higher resulting from the same springs but with different weight from front to rear. I was avoiding in my head removing the rears to cut shorter and came to the idea to carefully heat the coil in upper perch while still installed allowing it to bend and lower the ride height. It's a little sketchy but doable.

 

[TOBASH]

NEVER DO THAT! It is unpredictable and can lead to premature spring failure and loss of control. Either buy springs that are the correct height or properly shorten them, but do not take risky shortcuts. That kind of crap was done for years by unqualified DIY’ers, and created very unstable cars with springs that could crack or not respond properly. It also risks undercarriage fire.

Do it right or don’t do it at all.

 

[jrtoffroad]

Got the fronts installed a last week. I wasn't there for the front install but they said they couldn't the front in full length and cut 1 coil off same as we did on the rear. I haven't measured it to see actual lift and haven't driven it much. I plan to use a fair amount this week and will post results.

JRT are there any other options I need to know on the 5125? You said they were too light. Can you elaborate? I'm basically a mall crawler but do go offroading. It's mainly slow cruising and slow flexy offroading. No mid/high speed offroad stuff.

Bilstein 5125 Offroad Shocks - ShockWarehouse

The 5125 Series offers Bilstein technology for custom applications. 5125 Series shocks feature Bilstein's superior single tube high gas pressure design for the up most in consistent fade-free performance and long life. Bilstein's patented Deflective self-adjusting valving delivers improved...

www.shockwarehouse.com

They couldn't get it installed? Did they not have a spring compressor? I'm curious to hear how the ride height turns out. Might want to cut a little more off the rear springs to level it (I think you cut 1 coil off the rear too, right?)

The bilsteins I used only come in a 255/70 valving. In my opinion this is not enough for our relatively heavy rigs, especially the rebound. In some shock lengths Bilstein offers a 360/80 valving which I think would be much better for our applications. Really, it comes down to trying to controling the spring rate. The more spring rate, the more rebound you need to dampen the response to compression. Although my Humvee rides well, body roll in corners is a bit exagerated and it is a bit 'bouncy' after a large bump taking a couple oscillations to reach steady state again.

 

[Glider]

They couldn't get it installed? Did they not have a spring compressor? I'm curious to hear how the ride height turns out. Might want to cut a little more off the rear springs to level it (I think you cut 1 coil off the rear too, right?)

The bilsteins I used only come in a 255/70 valving. In my opinion this is not enough for our relatively heavy rigs, especially the rebound. In some shock lengths Bilstein offers a 360/80 valving which I think would be much better for our applications. Really, it comes down to trying to controling the spring rate. The more spring rate, the more rebound you need to dampen the response to compression. Although my Humvee rides well, body roll in corners is a bit exagerated and it is a bit 'bouncy' after a large bump taking a couple oscillations to reach steady state again.

It was the same shop, so not sure. I'm right at 25" from center of wheel to bottom of fender. If you look in the post above it looks like the length has to be specified. Each length has a sku# I'm guessing the one with a 11-12" compressed length. I really appreciate your help. I'll call when I'm sure and check on valving.

 

[jrtoffroad]

It was the same shop, so not sure. I'm right at 25" from center of wheel to bottom of fender. If you look in the post above it looks like the length has to be specified. Each length has a sku# I'm guessing the one with a 11-12" compressed length. I really appreciate your help. I'll call when I'm sure and check on valving.

25" is a nice height. Not much down travel, but very good clearance and should have lots of compression with the softer spring rate. BTW, if you haven't tried it, pull the sway bar sometime and see what a big difference it makes in articulation. I actually always run mine without the sway.

From your link above, the shocks I'm running are the 33-062518 with bumpstops added. As I think I mentioned earlier in this thread, you'll also need limit straps if you run a longer shock like this. I lost the lower mount on one of my front limitstraps recently and ended up with a bent tie rod end when it over extended while turning and acticulating offroad.

 

[Glider]

Can you think of any reasons why I couldn't run a limit strap inside the spring and use the 1/2 shock bolts for mounting points. I would just need to get the right length.

 

[jrtoffroad]

Can you think of any reasons why I couldn't run a limit strap inside the spring and use the 1/2 shock bolts for mounting points. I would just need to get the right length.

It would sure be nice if that could work, but I'm not sure if you'd be able to get a straight shot top to bottom, I think the shock body would get in the way.

 

[AtlantaSBR]

@jrtoffroad @Glider After driving a bunch more in the rig I have decided it is time to swap springs in my M1097A2. I have the MAK springs still installed and nothing compresses them and the ride is rough. If you were to do it again would you go with the 4WD Armada springs (MOOG 81085)?

Would you do that at all four corners or a different mix? Don't want to waste a ton of money on something but my rig is mainly a weekend vehicle to home depot and cruising around town. I would like to take it off-roading but haven't yet.

 

[Glider]

I really am happy with the springs. I can't remember part number but yes armada springs part number as recommended to me earlier. I would cut 1 1/2 coil for front and cut 2 coils on rear. I haven't changed shocks yet. I'm told they will make a big difference and am inclined to believe it. I have the material to convert to truck shocks but haven't taken time to do it. I also do not have runflats so there could be variance in ride.

 

[AtlantaSBR]

I wonder if it matters on the amount of sprint cut off if you have the cast vs sheetmetal brackets. My truck has the welded sheet metal. Hopefully jrt can chime in on that.

 

[Glider]

It's covered in the thread if I remember correctly.

 

[jrtoffroad]

I wonder if it matters on the amount of sprint cut off if you have the cast vs sheetmetal brackets. My truck has the welded sheet metal. Hopefully jrt can chime in on that.

Yes, you'll need longer springs with the cast rear mounts. Although I haven't tried this configuration, I'd recommend starting with no more than 1 coil cut in the rear with the cast mounts (honestly, I'd start with no coils and go from there, hard to put them back on )

 

[AtlantaSBR]

Yes, you'll need longer springs with the cast rear mounts. Although I haven't tried this configuration, I'd recommend starting with no more than 1 coil cut in the rear with the cast mounts (honestly, I'd start with no coils and go from there, hard to put them back on )

Ok, I have the welded so I will start with a coil cut off and see. Thanks need to soften this ride up and I would rather make a mistake on these than the real ones that cost 50% more

 

[jrtoffroad]

Real what, springs?

Springs make a big difference, but shocks are the 2nd part of the equation. The stiff stock shocks also cause a very firm ride even with soft springs.

 

[LouWon]

The coils are one part of the problem, you need to get away from the OEM shocks
I did do a review on Dick Cepek Shocks, you can even adjust them on the fly, nice stuff
look at the thread
Humvee shock absorber and spring options?

 

[rolling18]

Just curious, What model HMMWV do you have? Any idea what springs those are, or how heavy it is?

You're probably the only owner I know who is happy with the ride with stock springs. My M1123 felt like it had no suspension and would nearly pickup a tire driving on a big curb. Rough terrain at any kind of speed physically hurt.

I TOTALLY agree with this!
mine has a literal "crash/ bang over anything larger than expansion joints on the freeway...
and thats on 20 PSI!

I have the 1123 heavy varient, BUT its only the 2 door soft top, so no weight and scales 6400 full tank.... no runflast with alloy wheels

 

[Mogman]

I TOTALLY agree with this!
mine has a literal "crash/ bang over anything larger than expansion joints on the freeway...
and thats on 20 PSI!

I have the 1123 heavy varient, BUT its only the 2 door soft top, so no weight and scales 6400 full tank.... no runflast with alloy wheels

That's 1,200lb more than my M998 2 door and that was with stock wheels and run flats, I wonder where all that weight comes from? of course I have a Dmax and Allison but I would not think there would be much difference there.

 

[SmartDrug]

That's 1,200lb more than my M998 2 door and that was with stock wheels and run flats, I wonder where all that weight comes from? of course I have a Dmax and Allison but I would not think there would be much difference there.

If it’s anything like my M1123, it’s likely due to the additional 500lbs of black undercoating that covers EVERYTHING underneath.

Seriously though, I’m interested in hearing why as well.