Another rear suspension question...

I am sorry to ask another lift question..but here goes. I have an 04 DC and I am in the process of replacing the suspension all around. The suspension parts I have are all fairly old (10yrs) with 120k+ miles. Up front I have an OME setup with ¼ top plate. I have already ordered the replacement assembly from Wheelers and it will be here next week.


Over the winter I replaced my leaf springs with Dakars (no AAL.. yet) and I am still running the Bilistien 5125s in the rear (going to replace).


I am ready to order the rear suspension and plan to add the OME AAL to help with the weight in the rear. With help from another TW buddy, I will hopefully put these on by the end of the summer. My questions are regarding the rear shocks:

1. The Bilsteins in the rear are f4-be5-6253-h5 5125 series (see pic). Neither Wheelers or Toytec show these as options in their kits. They have Bilstieins but not with the number above and Toytec has two options. I was happy with the performance of these (there still there) and I can find them on Amazon. Has the number changed? Which ones should I order if I go with Bilistien?
   
   
2. I was also thinking about trying the . I know OME is designed to work with OME but wanted to see if anyone had experience with both and will they work with the Dakar and AAL?
   
   
3. Last question. Do I need a longer leaf spring center pin when adding the AAL or will the one that came with the Dakars work?
   

Thanks for any insight!

 

Holy shit that's a lot to read.

Bilstein 5100's are just overall popular amongst all vehicle models, so naturally, they're the most often chosen shock for "kits"

A 5125, 6125, etc. are an 'upgrade' from there.

With all that weight, I'd vote you go with a custom leaf pack.

And I don't know about you, but with even less weight than what you're carrying, I found Bilstein 5100's to be way too soft in the rear paired with my OME Dakar leaf pack.

I run Fox 2.0 universal in the rear and with the bed loaded, they're amazing over washboards and off road in general.

 

I have the Dakars and the nitrochargers in the rear of my 98 xtra cab. Rarely carry around a lot of weight, just a topper.

99% of my driving is on road with minimal weight in the bed. That combo is nice but it’s a bit stiff for daily driving.

Loaded up with weight on a trail? Butter. So nice.

On my 04 I’m going to go with Dakars in the rear paired with Bilstein 5125 with the 170/60 valving.

Because I’m looking for a softer ride for the vast majority of my driving. I’ll deal with bro lean and a bit of sponginess on the trail loaded up. Hell I explored for over a decade on the original suspension with 182,000 miles on it.

 

Thanks for the feedback so far.

 

Have the OME suspension kit with the Dakars, Like Madjik_man the truck is a daily driver and I have a 31 Mi commute one way and a 3rd of it is dirt road. That being said after the install the ride was really stiff plus it gave the truck a 70's muscle car rake with the rear end way higher than I wanted it to be. Even after installation of really heavy front and rear aftermarket bumpers it still rode stiff, so I removed the 3rd spring from the rear pack and it brought the rear down almost level with the front and the ride has since been way nicer, even with a load in the back (550 Lb motorcycle) the sag is very minimal. Eventually will go with the Bilstein 5125's when a replacement is warranted but for now the OME's are working out great.

Truck with 3rd leaf removed.......

 

OME and Bilsteins are very, VERY different animals. I had the 5100s on my last truck, and just installed Nitrocharger Sports on my current truck.

In general, the OME's are better tuned for offroad use, while the Billies offer some specific strengths on pavement and are much more rust resistant.

More specifically:

Both brands transmit a fair amount of vibration from the little bumps through the chassis on the road. But that is where the similarity ends.

The billies are digressive and take fast corners and emergency swerves on pavement far better than the OME's, and they also hold the nose up better in hard braking. The flip side to that is they didn't hold the rear down well in heavy braking (they let the rear leafs droop out fast), so my truck felt like it was standing up on its nose more than suffering from nose dive. At times the bilsteins could not keep up in whoops and caused bucking to sneak up on me, and blasting down unmaintained fire roads rearranged everything in my truck (1st gen) and felt like they could chip my teeth. On bigger, slower rocks, the 5100s felt good enough.

In contrast, the OMEs are progressively valved, which produces a lot more more body roll in hard cornering and emergency maneuvering. It's not uncontrollable, but it's alarming to a driver who has gotten accustomed to digressively valved cornering. But excessive body roll is also typical for suspensions tuned for offroad, and OME will accordingly be more compliant in slower, flexy terrain. OME also seems to have a trick up its sleeve, in that the Nitrocharger Sports are more heavily damped on the rebound, which holds an unloaded truck bed down in hard braking, even as the front might sink. I don't have the correct coil springs for my truck on the front yet, so I'll have to revisit their braking performance after I do.

I will also be hitting some fire roads on Thursday and Friday, so will have a better idea how the OME's perform on small high frequency bumps after that. (And I won't have a chance to drive some desert whoops with the OME's for a few months, but am not expecting miracles from a shock that can't be tuned.)

So far, I think the body roll is a fair tradeoff, and I definitely prefer Old Man Emu at the rear axle.

Importantly, measure your stuff and droop lengths after installing the AAL before you buy shocks. You might find that that OME is not long enough.

Side notes: The OME bushings are oversized. Plan on greasing them and beating them into the rear lower shock mounts with a mallet.

And the rust issue is pretty annoying. I picked up my OME's from a guy who had moved up to tunable shocks, and although the OME's only have 12,000 miles on them, they look like they came off a tractor from the 1970s. The Pantone color for OME yellow is 116 U when (not if) it comes time to repaint them.

I also had the skyjacker m95s on my radar for rear shocks, but I can find zero info on their valving.

 

Very detailed and helpful. Thanks!!

 

I just finished up adding a AAL to my factory leafs, the center pin that came with it was roughly 4 1/2 inches long. Hopefully that will help you a little with one question. I also needed 6.75inch ubolts for the extra leaf.

 

Running full OME.
Dakkar with the extra leaf in the rear. If I'm not mistaken, longer center pins are provided with the aal.

Also running nitrochargers sports with 881 coils up front. Tube bumper and winch.

Just a tiregate prerunner spare tire carrier in the rear. Sometimes a tool box with about 400# of gear, sometimes not.

Edit: as the above poster stated. Longer u bolts.

 

My AAL from toytec came with 2 new center pins.

 

So I ran some fire roads and the OME's did fine on washboard. They are definitely less harsh than the 5100s I had on my previous truck, and they respond okay to hitting rocks in the road too. Big holes, on the other hand, were hard. It felt like the back of the truck dropped into them. If the rear shocks being more heavily damped on the rebound helps keep the suspension tight in hard braking, they may also be preventing the wheels from dropping fast enough into big holes, so the rear frame drops too. I would not say either the Bilsteins or the OME's do well with holes, but the OME's do better with washboard.

I also played with the body roll more, and the OME's do let the truck roll more in a hard swerve than Bilsteins, but you have to jerk the wheel pretty hard to find out. Most of the time it's not bad.

 

Nicely done on this and your earlier assessment of the Bilsteins. I have the 5100's and would agree. The reasons stated went into my decision to purchase the set. Inexpensive, good on road where my truck mostly lives, and acceptable offroad performance. My truck does get offroad almost every day on rough and muddy construction roads and the 5100's are just fine.

I will say the "bucking" on whoops can be jarring, but I can live with it since I only drive dunes a couple times a year.

@TomHGZ What is your spring setup in the back and how does it ride? I have slight takeoff vibes which I think (and have read) that tells me I need a stiffer setup.

For the record, I understand this is a 1st gen thread

 

Thanks @RoughRder. What do you mean by takeoff vibes?

This truck is new to me and I am still running stock springs in rear. But it also came with Firestone Ride-rite air bags installed by the previous owner, and the more I think about it, the more I wonder if they are tainting my observations. I ran the bags at various pressures last weekend, from nearly empty or at ~4-5psi, up to about ~20psi, to alternately try to eliminate their influence on the ride as a variable, but also to roughly simulate the stiffness the AALs on my 1st gen Tacoma would have given me on the fire roads, so I could compare the OMEs and the 5100s more equally.

But the more I think about it, the more I think the air bag system might be influencing the ride quality for a completely different reason: the air bag mounts clamp to the leaf packs fore and aft of the U-bolts, and I am thinking now that there is no way that does not inhibit the responsiveness of the leaves throughout their range. (Even with no pressure in the bags, I suspect the clamps inhibit the ability of the springs to arch and slide against each other.)

On the other hand, I have my recent experience with the stock TRD Sport shocks that immediately preceded my OME's, which I also used with the air bags, so a lot of my understanding of what is unique about OME shocks comes from baselining their performance immediately against stock shocks in an otherwise identical setup. I also baselined my experience of 5100's against original equipment Bilsteins on my 1st Gen Tacoma, so I think I can safely say the OME's and the 5100's contrast OE shocks in some divergent ways.

 

The vibes- basically, my rear spring isn’t strong enough to resist the torque and twists on takeoff, gets out of alignment briefly, and a slight vibration is felt between 5-10 mph. My AAL is short and I think that’s my problem, it’s not stiff enough to resist over twisting. With the 2nd gen 3 leaf stock suspension, prior to the TSB 4 leaf, many owners including myself had the notorious takeoff “bump.” This was the same principle, but could be mitigated (but not entirely eliminated) by properly adjusting the rear drums. The drum breaks loosen with wear and don’t hold the drum firm, when they engaged, the axle snapped forward since the springs were weak and the driver feels a rather nasty bump. More than once I thought I had been rear ended. An adjustment made it go away for me, but I needed a better suspension when I added my shell. Now I’m in the same spot as before considering better rear springs. I do need to adjust my drums again and hopefully it will go away, but no guarantees.

Loooooong story short, I’m doing research on a new setup for the rear and landed on this thread, hence the question.

hopefully for OP, a user with a higher end suspension comments so you can make a good decision. Also, I’m sure there are 10s of threads on this subject.

As far as the bags, I would be curious to know what the clamp bolts are torqued to. 2nd gen u-bolts are 36ftlbs, if the bags are torqued higher, I would be inclined to agree with your assessment.

Also, springs (coils, leafs, bags) handle weight, shocks/struts are responsible to recover the system and return it to normal position. I’m wondering if even at low pressure, the bags are just too stiff if you’re running empty.

 

The issue with the airbag mounts is they rigidly clamp the middle eight inches of the leaves onto the overload leaf, preventing eight inches of spring from flexing up or down. Removing the middle eight inches from play on a 42 inch spring is pretty detrimental. OEM u-bolt torque doesn't really factor. (I also ran the air bags at zero pressure against Firestone's advice, "for science". The main discovery was they stop compressing about .7 inches before what the OEM bump stops allowed.)

There is no way a short AAL on 2+1 leaves is doing you any favors. I got axle wrap regularly with single leaf AALs on 3+1 leaves and a four-banger.

 

Definitely stick with the 5125s I can get you the part number I have. The bushings are smaller and need to be drilled out or replaced. Also the lower shock mount needs to be replaced to get that extra shock travel.

I just ran through a full gas tank of 4 low with new 5125s and it was really really pleasant. It was a mix of very difficult rock sections and fire roads. Zero complaints .

One thing to note with 5100 fronts is the noise they make when they compress fast. It makes a noticable hissing sound. But only on hard hits or big drops, it sounded like I lost a bead the first time I heard it. But everything is fine. I'll have it on the lift tomorrow just to give everything a check up.

 

Good points, I can get on board with that assessment.

Yeah, another score for "buy once, cry once." Now I'm into "buy twice, take apart your rear end twice." The rear was much harder than the front IMO.