Don't swap the Med for Heavy OEM Springs

[Hayes]

We're definitely straying into territory here, but...

How does tire size itself affect shock fitment or travel, beyond bottoming out directly on your tires? If that's the case, you should be lowering your bump stops to limit up-travel. The only influence tire size has on suspension travel is where in the shocks range you start to rub fenders and frames.

I also respectfully disagree on standard OME shocks making things worse. My truck flexes much further with standard OME than it did on the factory shocks. The standard OME shocks are not "short," by any means.

L shocks may be 2" longer over all, but they're also 1" longer compressed. They net 1" additional travel in the shock, not 2.

The front end is definitely tight (compared to the rear at least). And short of fundamental changes in geometry (hitch-pin mod, etc.) it only flexes so far. Removing the front antisway bar and leaving the rear helps balance and loosen it up, but you can only get so much out of the system in terms of overall travel.

 

[Tools R Us]

... How does tire size itself affect shock fitment or travel, beyond bottoming out directly on your tires? If that's the case, you should be lowering your bump stops to limit up-travel. The only influence tire size has on suspension travel is where in the shocks range you start to rub fenders and frames. ...

Correct, but it all has to be taken into account. More flex = more axle angle = more tire angle = more potential for tire rub. Your running 315's with only superficial rubbing, add some longer shocks and that rub will increase. This is why stock rigs can often run 315's with little rub.

 

[Tools R Us]

I realize that there is extra travel in the L shock, but the L-shocks were not designed to be used with the 850/863 coils--these coils are too short. J springs, sure. On the rear with L shocks and 863 coils, the coils might get a little loose at full droop. ...

I agree that the L's were not designed to be used that way, one could successfully argue that the Cruiser wasn't "designed" to be lifted, who cares?

The point is that it works and works well. One of the most popular lifts locally is heavy rear with J front springs and L shocks all around. Making about a ~3.5" lift that is relatively level and flexes well. The added flex makes the rig more stable in cross axle, less wheel lift, has more even ground pressure on the tires, so is less dependent on lockers.

 

[Ebag333]

How does tire size itself affect shock fitment or travel, beyond bottoming out directly on your tires? If that's the case, you should be lowering your bump stops to limit up-travel. The only influence tire size has on suspension travel is where in the shocks range you start to rub fenders and frames.

The tire size directly affects how much room you have for travel. All else being equal (bump stops, lift, etc), you'll have more room for up travel with a 33" tire than you will with a 37" tire.

My 35" tires in the rear rub against the body at full stuff. They do not rub hard enough to be a problem, other than I might spray some bedliner in there once every couple years to pretty it up. That's with stock bump stops. There really isn't a need to drop the bump stops unless your tire rub is to the point where something will get damaged, or you will over compress your shocks.

L shocks may be 2" longer over all, but they're also 1" longer compressed. They net 1" additional travel in the shock, not 2.

That would be true assuming that you had to extend your bump stops to prevent over compressing the L shocks.

The truth of the matter is that for most of us, that assumption is false. You do not need to extend your bump stops as you will not over compress the L shock.

To give an example, lets say you're running 35's with stock bump stops (to keep it simple). You'll have about 16" of room with the tire fully stuffed. The OME standard shocks are 14.5" long when compressed, the OME L's are 15.5" long. So with this particular configuration, you can fit either shock without making any adjustment.

The standard OME's are 24.5" long fully extended, and the OME L's are 26.5" long fully extended. So by switching from the standard OME's to the L's you've gained two inches of extension and lost zero inches of compression....in other words your total travel goes up two inches, not one.

It all depends on how much room you have for the shock, which you should go out and measure on your rig as they vary slightly from rig to rig. But a rough estimate is 15" of room with 33's, 16" with 35's, and 17" with 37's. Dropping your bump stops, changing your lift, adding a body lift, changing the shock mounts....all that and more will change those numbers (some more than others), which is why you should cycle your suspension and measure it yourself.

You should take a look at the Pro-Comp shock thread. There's lots of good input from multiple parties on properly fitting shocks. It's really not as easy as it seems from the first glance, I know I've had my head spinning trying to figure out how they're going to fit with multiple adapters adjusting the length up and down.

The front end is definitely tight (compared to the rear at least). And short of fundamental changes in geometry (hitch-pin mod, etc.) it only flexes so far. Removing the front antisway bar and leaving the rear helps balance and loosen it up, but you can only get so much out of the system in terms of overall travel.

I don't think you'll ever get as much out of the front as you will with the rear, but I know you can flex it enough to max out 14" travel shocks without major mods. Considering the difference between a 14" travel shock and a 10" travel shock, that tells me that there is a lot more that the front end can do than it does in most people's setup. It's equivalent to putting strap limiters on the axle and saying you can't get any more flex because the strap is maxed out.

Personally I don't want my front to flex as much as the rear, that's why I'm running 12.5" travel shocks front and 14" travel rear. I've basically intentionally limited the front.

 

[Tools R Us]

Hmmm, I will think some more about the shocks then, I just figured with a body lift there be room for the L's a little bit more and they could be put to better use. I was thinking when it came to the body lift I was going to go with 4crawler's body lift, seems to be very thorough and have never heard bad about him.

Unless your going to run +37" tires, the body lift is going to little if anything from a tire fitting stand point. Most of the significant tire fitting issues are the tire sidewall to frame/inside of the fender wells.

Typical 315 rub:

 

[julstirn]

Ok so now that there's even more info on here to confuse me, haha! So is the verdict on the original topic that you can make heavies out of mediums true or would I need to just get new heavy springs? Also, I can fit and am fitting the 315 easy. The body lift was one way to keep the suspension lift down and save my self some major caster correction issues maybe. I was thinking that 2.5 lift keeps all within specs and have 3.5 inches total using one inch body lift as an inch of that. This way all flex can be used, plus use of shocks length and give me some benefits that a body lift can provide that suspension lift cant. I have mediums, just not sure weather or not to order heavies or order spacers/

 

[Tools R Us]

Kevin, can you please post the suspension specs (springs, shocks, bumpstops, caster correction, etc) of your truck. I would like to go the J springs route and would like to emulate your setup. Thanks.

That is kind of a tough one, it's a ~6yr evolution and lots of parts are handmade and measured by "about that big, just right to fit" method! Will likely leave some stuff out (forgotten) and measurements are "close/about".

The springs are J's with ~1.5" custom spacers in the front. Shocks are L's with ~1.5" spacers on the rear upper mounts. The caster correction is custom arms that have a radius arm on the right side and a link that only uses one axle end bushing on the left.

The rear has 3" stop spacers. The front has ~1.25" stop spacers that are on the lower coil mount. All sway bar links were cut and lengthened, ~1.5"? When the arms (more CC) and L shocks were added, the front needed more, a 3/8"? alloy block spacer was added. The front axle mounts have been rewelded to prevent breakage.

All of the rear links and both panhards are stock, the rear lowers have 1.5x.25" angle welded end to end. The driveshafts are stock, the rear is retubed with .120 wall.

The brake lines are all original, the frame side mounts are lowered to allow for flex. The e-brake cable mount was also lowered.

It's relatively light, close to stock ~5200lb? I don't carry much junk, so it sits at ~24.5" front and ~25" hub center to flare, so about 5" lift over stock? It handles and flexes well, is comfortable (my wife likes it, that's what matters) on the road and trail.

There are a few thing that I could tune, like have more bump stop than needed. But it works well, I prefer wheeling over working on it and any gains at this point would be relatively minor, so haven't found the motivation.

If I were doing it again, would strongly consider going with the heavy rear, J's front with L shocks. That setup works well and isn't as tall.

 

[snowcamo80]

Yeah, the evolution of how you built your rig around the Js and Ls - lots of posts to read.
I thought to make it easy on myself (and possibly others) to just ask you flat out. Thanks for the reply.

That is kind of a tough one, it's a ~6yr evolution and lots of parts are handmade and measured by "about that big, just right to fit" method! Will likely leave some stuff out (forgotten) and measurements are "close/about".

The springs are J's with ~1.5" custom spacers in the front. Shocks are L's with ~1.5" spacers on the rear upper mounts. The caster correction is custom arms that have a radius arm on the right side and a link that only uses one axle end bushing on the left.

The rear has 3" stop spacers. The front has ~1.25" stop spacers that are on the lower coil mount. All sway bar links were cut and lengthened, ~1.5"? When the arms (more CC) and L shocks were added, the front needed more, a 3/8"? alloy block spacer was added. The front axle mounts have been rewelded to prevent breakage.

All of the rear links and both panhards are stock, the rear lowers have 1.5x.25" angle welded end to end. The driveshafts are stock, the rear is retubed with .120 wall.

The brake lines are all original, the frame side mounts are lowered to allow for flex. The e-brake cable mount was also lowered.

It's relatively light, close to stock ~5200lb? I don't carry much junk, so it sits at ~24.5" front and ~25" hub center to flare, so about 5" lift over stock? It handles and flexes well, is comfortable (my wife likes it, that's what matters) on the road and trail.

There are a few thing that I could tune, like have more bump stop than needed. But it works well, I prefer wheeling over working on it and any gains at this point would be relatively minor, so haven't found the motivation.

If I were doing it again, would strongly consider going with the heavy rear, J's front with L shocks. That setup works well and isn't as tall.

 

[Ebag333]

Ok so now that there's even more info on here to confuse me, haha! So is the verdict on the original topic that you can make heavies out of mediums true or would I need to just get new heavy springs?

You can make heavies out of mediums by adding a spacer. That's essentially what I've done with my setup (you can click on the link in my sig to see specifics).

Since you already have the mediums, I'd just go ahead and put in a spacer. If you're wanting to buy springs, buy either heavies or J's.

Also, I can fit and am fitting the 315 easy. The body lift was one way to keep the suspension lift down and save my self some major caster correction issues maybe. I was thinking that 2.5 lift keeps all within specs and have 3.5 inches total using one inch body lift as an inch of that. This way all flex can be used, plus use of shocks length and give me some benefits that a body lift can provide that suspension lift cant.

Tools is right, there's not much that doing a body lift gives you in terms of lift. It does help slightly as you rub in a different spot...slightly lower which is also a bit further to the inside, but you're talking about fractions of an inch, not really worth talking about.

It helps a bit more in the front, but the front is difficult to get to rub anyway as it doesn't flex that much.

I'm a huge fan of body lifts, I'm actually going to be swapping my 1" out for a 2.25" one here shortly, but while I initially did it for tire clearance I've since realized that the additional tire clearance it gives is minimal.

There's lots of good reasons to do a body lift. Everything runs cooler (especially the tranny hump area). MUCH easier to get to stuff (the starter is a snap). Can raise your rear top shock adapters to fit long travel shocks without dropping the bump stops. You can do a drive train lift. It's an extremely cheap mod if you DIY, and merely cheap if you don't.

You can fit 315's on just medium springs (heck, stock if you don't mind some rubbing), so don't worry about fitting tires.

 

[julstirn]

Will the j's front and heavy rear be level then? And if I go the spacer route, is my best bet metal tech front? Who do I use for the rear?

 

[Hayes]

Agreed on all general points, with the proposed synopsis for the folks asking questions about lifts:

Lifting your truck is not a simple formula of A + B = C. There a lots of variables with lots of different outcomes. Heavy truck vs. light truck being an important one. My truck is pretty heavy, and with OME 850/863 coils and 0.5" spacers all the way around, my truck is level, and 2.5" higher than stock. Some folks get 3+ inches out of the "heavy" coils all by themselves. It depends on your truck and what you've got on it.

Rubbing seems to vary too. With 315/75R16 Goodyear MTR Kevlars on factory rims with factory bumpstops on the above lift, I get the inner rear wheel well rub shown in the photo above. However, before I added a 1" body lift, I also had a more problematic rub on the inside metal lip of the fender that was cutting the tires, as well as more pronounced contact in the front wheel wells. After a couple wheeling trips, I can confidently say that the 1" body lift has cured the problematic rubbing.

I'm very happy to run my low suspension lift (2.5") with 315's and zero rubbing problems on the factory bumpstops--I'm able to utilize the full range of motion offered by the standard OME shocks. With the wheeling I do (not extreme but not too shabby, either), I never lift tires. I'd worry about my coils getting loose with L-shocks, and I haven't found myself wanting more suspension travel.

There is a wide variety of approaches to fit a wide variety of needs.
Have fun.

 

[Tools R Us]

Will the j's front and heavy rear be level then?

In my experience, heavy rear lifts ~4" and J front ~3.5" on a close to stock weight rig. So pretty much level with some capacity for cargo before getting saggy butt syndrome.

One of the advantages of OME is tons of spring selection. If/as your build changes swapping is easy and resale is a snap.

And if I go the spacer route, is my best bet metal tech front? Who do I use for the rear?

If you select the correct springs, there is no need for spacers. I wouldn't run spacers on stock springs, IMHO they are too soft at stock height. Metal Tech makes good spacers. On the front there are two types of spacers, those that go over the stop/cone (like Metal Tech) and those that go in with the spring, both have advantages, depending on the application.

 

[julstirn]

I might be leaning towards the j front heavy rear set up, but then i gotta start thinking caster correction which was one thing i liked bout small 2.5 lift

 

[Grench]

Cheapest way is to source the UHMW from Grainger or somewhere similar. Prolly $30 or less if you can get a couple people to go in with you so you don't have to buy 3' of UHMW just for yourself.

Right... I looked up UHMW. Ultra-high-molecular-weight polyethylene. AKA very dense plastic. OK, so what specs on the stock? Diameter, hole size, etc...?

I'm height limited by my garage door. But I would like just a touch of body lift for a slight rub on my 315s under bounce - I was thinking 1/2" or 3/4". I might be able to do 1" but I need to get out the calipers at that point.

My garage looks like it is giving birth when I back my truck out already. If I park it inside for long, my neighbors ask me, "Didja get rid of your truck?" They can't seem to put the concept in mind of it actually fitting inside a garage. Full tanks and recovery gear loaded, I clear by ~2.5". Empty tanks and empty truck it's around 1".

 

[Ebag333]

Right... I looked up UHMW. Ultra-high-molecular-weight polyethylene. AKA very dense plastic. OK, so what specs on the stock? Diameter, hole size, etc...?

3' Lengths
White: Item # 1UXD5
Black: Item # 1YVL4

If you want 6' lengths, figure it out yourself.

The specs are the same for white or black so I ordered black. I believe white is a higher grade than black, but don't quote me on that.

I don't remember the bolt size, Roger Brown references 7/16" in his guide.

I'm height limited by my garage door. But I would like just a touch of body lift for a slight rub on my 315s under bounce - I was thinking 1/2" or 3/4". I might be able to do 1" but I need to get out the calipers at that point.

My garage looks like it is giving birth when I back my truck out already. If I park it inside for long, my neighbors ask me, "Didja get rid of your truck?" They can't seem to put the concept in mind of it actually fitting inside a garage. Full tanks and recovery gear loaded, I clear by ~2.5". Empty tanks and empty truck it's around 1".

If you have a winch with cable you could run it under your axles and use it to lower your suspension.....

 

[Hayes]

Mod your garage.

Right... I looked up UHMW. Ultra-high-molecular-weight polyethylene. AKA very dense plastic. OK, so what specs on the stock? Diameter, hole size, etc...?

I'm height limited by my garage door. But I would like just a touch of body lift for a slight rub on my 315s under bounce - I was thinking 1/2" or 3/4". I might be able to do 1" but I need to get out the calipers at that point.

My garage looks like it is giving birth when I back my truck out already. If I park it inside for long, my neighbors ask me, "Didja get rid of your truck?" They can't seem to put the concept in mind of it actually fitting inside a garage. Full tanks and recovery gear loaded, I clear by ~2.5". Empty tanks and empty truck it's around 1".

 

[julstirn]

Quick clarification? On the J front and heavy rear setup, my question is are the rears the 863 or the 863J?

 

[Hayes]

Quick clarification? On the J front and heavy rear setup, my question is are the rears the 863 or the 863J?

"Regular" heavy rears are 863.

J heavy rears are 863J.

 

[julstirn]

I'm referring to post 112 where we are talking about the j front and heavy rear setup. I was wondering what heavies we are talking about I assume the 863J since he said it was about 4 inches of lift for rear? Any comments on this!

 

[Tools R Us]

I'm referring to post 112 where we are talking about the j front and heavy rear setup. I was wondering what heavies we are talking about I assume the 863J since he said it was about 4 inches of lift for rear? Any comments on this!

Regular heavy rears 863 with 850J on the front.