Dobinsons IMS Vs. Bilstein 6112 (1 Viewer)

[TheYetiGXOR]

So I have been trying to do my due diligence and search and read as much as I can. I’ve get a new to me mint condition 08 blizzard pearl w/ 147K on the clock. I’m love planning out what upgrades I am going to do and to be honest I obsess over it a little. I want to make sure I am always making the informed decision when I buy things, this unfortunately leads to hours and hours of research before I pull the trigger. This however means I rarely ever have buyers remorse.

At this point in my search I have gotten to narrow it down to these two suspensions which I’m hoping to get some feedback on from everyone. These were picked based on there price point and features they offered, along with everyone’s recommendations.

On one hand we have the tried and true Dobinsons IMS. This kit is known by many and loved my many. I don’t think I need to say much more.

On the other hand we have the Bilstein 6112/5160 combo. This is the one that intrigues me. It has the larger body diameter(heat dissipation), has the option for a 650lb spring up front, remote reservoir in the rear, and the rear can be paired with a 675V Dobinsons coil. The issue is I don’t see many people running this setup and to be honest I’m not really sure why not. On paper it seems to all add up to be a really good setup. Is there something I’m missing here?

Let me know what everything thinks about this matchup and who will come out ahead in tonight’s head to head suspension cage fight.

 

[Jstawgn]

6112 is very good shock. The 5160 on the other hand is not that reliable. It's the same as 5100 series with additional piggy back. There are quite a few reports about it leaking within short periods of time.

The IMS been getting pretty good review. The adjustability of the spring height and robust lower mounting point is a plus. Plus available with long travel of you desire. The non adjustable seems to be a lot less complex than MRR Adjustable.

 

[HomersCanyonero]

I’ve been running 6112s upfront with the 600# springs since I bought it over 4 years ago and over 40k miles. It’s buttery smooth upfront and no issues. I don’t have added weight, but I do have skid plates, recovery points, and 285s.

I ran these 6112s with a variety of rears. First couple of years with the stock rear airbags and stock rear shocks, then switched the rear shocks to OME (bad combo), and finally converted to dobinson 675v rear coils with extended MetalTechs Icon 56550 rear shocks.

I have an extensive build thread in my signature with some off-roading videos/photos, but overall I’m very happy with the performance and reliability (no need to rebuild) of the 6112s.

And there are YouTube videos by suspension vendors like Shock Surplus that say the 6112s are one of the best values out there.

Unfortunately, i don’t have any experience with the IMS so I can’t compare.

 

[1ounce]

I have a similar decision to make but I'm leaning strongly towards IMS. Seems to be more user reports and I like that its a complete "system" rather than mixing parts from different mfgs. EG I know the IMS setup will work well out of the box.

 

[TheYetiGXOR]

I’ve been running 6112s upfront with the 600# springs since I bought it over 4 years ago and over 40k miles. It’s buttery smooth upfront and no issues. I don’t have added weight, but I do have skid plates, recovery points, and 285s.

I ran these 6112s with a variety of rears. First couple of years with the stock rear airbags and stock rear shocks, then switched the rear shocks to OME (bad combo), and finally converted to dobinson 675v rear coils with extended MetalTechs Icon 56550 rear shocks.

I have an extensive build thread in my signature with some off-roading videos/photos, but overall I’m very happy with the performance and reliability (no need to rebuild) of the 6112s.

And there are YouTube videos by suspension vendors like Shock Surplus that say the 6112s are one of the best values out there.

Unfortunately, i don’t have any experience with the IMS so I can’t compare.

Are there any drawbacks to an LT setup? I understand that you need longer brake lines and different end links but is that about it? Are there any other considerations with a LT kit?

 

[HomersCanyonero]

The long travel rear just needs these considerations if just lifting 2.5” or so:

1. Extended rear brake lines
2. Longer rear sway bar end links
3. Upgraded rear bump stops

All these are marginally needed on a lift like mine. Higher lifts may require more changes.

And to get even more rear articulation, you might need to disconnect the rear sway bars.

 

[Shpnout]

6112's with 650lb springs is a great set up. 15% stiffer than stock. I ran these with 5160 and metal tech springs, also 15% stiffer than stock. Fronts now support a bumper and aluminum skid plates, sit at max height adjustment. I estimate 2+" of lift. Rides great. The 5160s seem just a little soft on compression, tho I will say, that now that I have just changed to OME mid stiff springs the shock seems to do better. ( I recently added a swing out arrangement). The metal springs are now listed for sale and a great starting point as you work thru the build up, PM if interested.

 

[NJGX]

I have been running the 6112/5160 combo for about a year now. I got the heavier 650lb front springs and Dobinsons 677V rears knowing I was going to add extra weight down the line. Stock bumpers and weight it rode perfectly fine, but a little on the firm side. Now that I have front and rear bumpers, storage drawer, and a winch, I am very pleased with the setup. I am at the top circlip notch on the front drivers side, second to highest on front passenger. I also have a 15mm spacer on the rear drivers spring to correct some lean. Even with the extra height, weight, and no front sway bar, it still feels planted on road as long as I drive responsibly and don't pretend to be driving a sports car. I went with this setup over others for value and availability at the time of purchasing.

 

[TheYetiGXOR]

The long travel rear just needs these considerations if just lifting 2.5” or so:

1. Extended rear brake lines
2. Longer rear sway bar end links
3. Upgraded rear bump stops

All these are marginally needed on a lift like mine. Higher lifts may require more changes.

And to get even more rear articulation, you might need to disconnect the rear sway bars.

How does this setup do on something like washboards? That was the biggest appeal for the 5160, the piggyback reservoir hopefully would help with heat dissipation.

 

[1ounce]

How does this setup do on something like washboards? That was the biggest appeal for the 5160, the piggyback reservoir hopefully would help with heat dissipation.

If you plan to hit a lot of washboards and you want to get over them fast, reservoir shocks are a must.

 

[Jstawgn]

If you plan to hit a lot of washboards and you want to get over them fast, reservoir shocks are a must.

Off the shelf Long travel rear shock is not such a great idea for high speed washboard since they require 2-3" extended bumpstop. Basically you would hit the bumpstop a lot sooner.

 

[Bralow]

I have been running the 6112/5160 combo for about a year now. I got the heavier 650lb front springs and Dobinsons 677V rears knowing I was going to add extra weight down the line. Stock bumpers and weight it rode perfectly fine, but a little on the firm side. Now that I have front and rear bumpers, storage drawer, and a winch, I am very pleased with the setup. I am at the top circlip notch on the front drivers side, second to highest on front passenger. I also have a 15mm spacer on the rear drivers spring to correct some lean. Even with the extra height, weight, and no front sway bar, it still feels planted on road as long as I drive responsibly and don't pretend to be driving a sports car. I went with this setup over others for value and availability at the time of purchasing.

@NJGX - How sure are you that you have 650lb front springs?

The reason I ask is because I have this same setup: 6112/5160 but with 675v in the rear. and I THOUGHT I had 650s in the front.

It was recently discovered on the GXOR group that the 6112s are actually 700lb springs - depending on which model you got.

The error is specifically because Battleborn is selling the assembled 6112s as 650lbs, but multiple people have called Bilstein directly and confimed based on the spring part number that it is actually a 700lb spring.



Just thought you might like to know.

 

[TheYetiGXOR]

@NJGX - How sure are you that you have 650lb front springs?

The reason I ask is because I have this same setup: 6112/5160 but with 675v in the rear. and I THOUGHT I had 650s in the front.

It was recently discovered on the GXOR group that the 6112s are actually 700lb springs - depending on which model you got.

The error is specifically because Battleborn is selling the assembled 6112s as 650lbs, but multiple people have called Bilstein directly and confimed based on the spring part number that it is actually a 700lb spring.



Just thought you might like to know.

So with that being said the 600lb 6112 is 46-227287 and the 700lb is 47-284142? If I am stock with no bumper or added weight I should run the 600lb?

 

[TheYetiGXOR]

So with that being said the 600lb 6112 is 46-227287 and the 700lb is 47-284142? If I am stock with no bumper or added weight I should run the 600lb?On antoher note that i just realizd

I also just realized that the baseline for these numbers is the FJ which is a V6. With that being said shouldn't our heavier V8 be paired with the 700lb spring?

 

[HomersCanyonero]

Re: remote reservoir shocks for washboards

I would argue that 2.5” vs 2.0” diameter shocks also make a difference in the amount of oil in the shock to handle washboard roads. So, it’s not just remote reservoir.

So, if you are desert racing the Baja 1000, then get Kings 2.5” with remote reservoirs. And you might need a custom setup as well with more upgrades.

I’m doing over landing with some medium difficulty trails (some rocks and some washboards, but not racing). rock crawling doesn’t need remote reservoir per se. Nor the washboard areas I encounter at non-racing speeds.so the 2.6” diameter 6112s have more oil than the 2.0” diameters with the remote reservoir. Require no rebuild and have been reliable (no leaks) in 4+ years and over 40k miles with over a dozen or so off road trips (some multi day overnight trips).

Re: 600#, 650#, 700# front coils on 6112s

it all depends on added weight. I haven’t seen official stock oem front coil lbs/in but I’ve seen guesses that they are around 580 to 590. The 600# are perfect for a stock weight gx470 and that’s what I have. And I’ve read that 650# if you add a front bumper or winch, and 700# if you add both.

Re: rear coils
Lift, weight and intended use determine what’s best for you. Most people cycle through different shocks and coils because their weight and needs change. Also, the ride feel is very subjective to each person.

people who get the same brand shocks/coils still have to make changes if their weight needs change or their ride height/comfort needs change.

if you can adjust the shock comfort and the height of the coils on the fly (oh wait, that’s the stock electronic shocks and rear airbags in gx470), then you can mitigate some of your changing needs.

 

[Bralow]

I also just realized that the baseline for these numbers is the FJ which is a V6. With that being said shouldn't our heavier V8 be paired with the 700lb spring?

It's more confusing than that: The lift heights they advertise are already accounting for a Front Bumpber, Winch, and Rear bumper. according to their documentation:

https://productdesk.cart.bilsteinus.com/media/products/bilstein/E4-WM5-Y601A00_2.pdf

As far as I know there is no 650lb spring available from Bilstein. You can get the 600 or 700.

So all in all:
Get the 600s if you are staying stock weight
Get the 700s if you are adding weight
You'll have to figure out the lift-heights per-clip setting based on your own situation

 

[NJGX]

I also just realized that the baseline for these numbers is the FJ which is a V6. With that being said shouldn't our heavier V8 be paired with the 700lb spring?

I guess I have 700 lb springs then lol. I did get the 6112s with heavy "650" springs from Battleborn (would not recommend) last year shortly after they launched. For stock, I would still go with the heavier rate springs vs the 600 lb ones. The FJ was a lot lighter than the GX thanks to the v8 and heavier body (500+ lb total difference). I think you'd be hitting bump stops all the time on 600 springs. Like I said earlier though, the ride with what I guess is the 700 lb springs is perfectly fine, just more firm than the 10 year old oem ones I replaced. I can't recall what perches I set them on before the bumper/winch, but it was somewhere in the middle. 650s would probably be the sweet spot for a stock GX though.

 

[HomersCanyonero]

I have 600# upfront and I’m not hitting the bump stops at all. I’m lifted about 2.25” upfront on the second from the top clip. I have aluminum skid plates, 285s, and apex tow points. So, not a lot of extra weight upfront, but more than stock.

And I measure my front lift from the middle of the hub to the bottom of fender. Nobody has the official measurements for a stock gx470 when new, but it seems it was at 20.25” hub to fender in the front. Stock rear was around 21” when new.


Mine hub to fender with 6112s/600 lbs/in coils and tricked rear airbags:

FD = 22.50” 3/22/19

FP = 22.75” 3/22/19

RD = 22.375” 3/22/19

RP = 22.625” 3/22/19

I do have a lean.

I don’t know how many people with 6112s and 600# or 700# coils have details on their lift, but I’ve been detailing my build for a handful of years in a way that comparisons can be made.

Maybe you can search for hub to fender measurements to see what else is available across all mfgs. Even dobinson has a lack of information when it comes to lift heights on gx470 and I’ve had to refer to the 4Runner info.

My 675v rear coils seem to compress too easily about an 1” too much when I load up my camping gear, but sit great with just 4 passengers. Im not complaining about the ride since it rides comfortably...just that they quickly sit lower than the font with just my camping gear.

 

[HomersCanyonero]

Oooops. Those rear measurements (with tricked rear airbags) in 2019 were prior to converting to 675v coils and icon 56550 shocks.


01/04/2020 Very empty with middle and 3rd row seats out:

RD = 23.625
RP = 23.875

 

[HomersCanyonero]

And one more point. The spring rate on coils is measured in lbs/in not just pounds.

So, don’t confuse that a coil at 600 lbs/in can carry 100 lbs less than a 700 lbs/in coil.