Dobinsons 5th Gen T4R Suspension options - from Exit Offroad

[Crikeymike]

Does having the adjustable shocks make the MRR able to be progressive, digressive, and linear? Or just different levels of progressive because it uses a progressive valve?

Progressive. The more they compress, the firmer they get.

 

[Secretarynotsure]

Yes I know how progressive works. I asked if having the 3 way adjustments makes the shock able to be also linear and digressive because you're able yo change the the high and low compression or if it is just different firmness of progressive and essentially just changes the curve of the progressive line because it's a progressive valve.

 

[Crikeymike]

Yes I know how progressive works. I asked if having the 3 way adjustments makes the shock able to be also linear and digressive because you're able yo change the the high and low compression or if it is just different firmness of progressive and essentially just changes the curve of the progressive line because it's a progressive valve.

Progressive is in the piston and the way it functions on the inside. Digressive is a different animal, as you already know.

Changing the 3 valving adjustments makes them softer or firmer in each of their own ways, but it doesn't change the way the piston operates. It modulates the speed at which the oil can flow through the HSC, LSC or Reb valves.

 

[CrawlCulture]

Does anybody have a good way to to calculate how much your wheelbase will change with adjustments of the rear trailing arms?

I need to bring my pinion down to the correct angle but I also want to extend the wheelbase by 1/8-1/4" to keep my tires off the rear door portion of the fender flare when it is fully compressed so I was wondering if extending only the lowers (keeping the uppers at stock length) will help get the pinion angle closer to factory and push the axle back just ever so slightly. I feel like that should work but I can't find any dimensions or info that I can use to figure it out with math and stuff :rain:. Thanks

 

[Crikeymike]

Does anybody have a good way to to calculate how much your wheelbase will change with adjustments of the rear trailing arms?

I need to bring my pinion down to the correct angle but I also want to extend the wheelbase by 1/8-1/4" to keep my tires off the rear door portion of the fender flare when it is fully compressed so I was wondering if extending only the lowers (keeping the uppers at stock length) will help get the pinion angle closer to factory and push the axle back just ever so slightly. I feel like that should work but I can't find any dimensions or info that I can use to figure it out with math and stuff :rain:. Thanks

If you push the lowers 1/4", it would add that much wheelbase but when you lift these, the wheelbase slightly decreases at ride height. It's not a question or concern I've ever had before.

Yes if you extend just the lowers it would dip the pinion down

 

[CrawlCulture]

If you push the lowers 1/4", it would add that much wheelbase but when you lift these, the wheelbase slightly decreases at ride height. It's not a question or concern I've ever had before.

Yes if you extend just the lowers it would dip the pinion down

Maybe I'm looking at it wrong but the reason I am looking to "stretch" it slightly is that ever since I have had the 35s on, at full compression in the rear (and it really takes a little bit of a bounce *timben bump stops*) the tires just barely touch the piece fender flare that runs along the back door. Every time I go out it pops it out of its clip and I was hoping I could push the axle back just a little to prevent losing that piece or having to do any trimming on the rear fender. The other side (back side) is a metal bumper and basically just open space so if it barely rubs that, it is just a matter of throwing a little paint on it every now and then. So that is basically why I would want to do it and I was just seeing if that would be the best way to accomplish that.

Makes sense? I figured I was accomplishing 2 things at once since the pinion angle needs a little adjustment too. Also, I thought maybe if you added length to just the bottom it would move on an arch and not a straight line since the top of axle is still held in place by the upper links. That's why I was thinking math but if I don't have to do it, hell yea.

 

[Crikeymike]

Maybe I'm looking at it wrong but the reason I am looking to "stretch" it slightly is that ever since I have had the 35s on, at full compression in the rear (and it really takes a little bit of a bounce *timben bump stops*) the tires just barely touch the piece fender flare that runs along the back door. Every time I go out it pops it out of its clip and I was hoping I could push the axle back just a little to prevent losing that piece or having to do any trimming on the rear fender. The other side (back side) is a metal bumper and basically just open space so if it barely rubs that, it is just a matter of throwing a little paint on it every now and then. So that is basically why I would want to do it and I was just seeing if that would be the best way to accomplish that.

Makes sense? I figured I was accomplishing 2 things at once since the pinion angle needs a little adjustment too. Also, I thought maybe if you added length to just the bottom it would move on an arch and not a straight line since the top of axle is still held in place by the upper links. That's why I was thinking math but if I don't have to do it, hell yea.

You're on the right track. Adjustable arms are the only way to change the centering of the tire and also the arc of motion, so since you'll definitely have to play around with it a good bit, I recommend upper and lower arms. Your stock upper arm on the driver's side is possibly hitting your gas tank at full droop too, depending what suspension setup you're running.

 

[pwflaherty87]

Hey Mike,

I've been running 302/700 725/701 for about 3.5 years now. 2020 with KDSS. The rear tends to sag just slightly and I've considered going up a step in rear coils. Which coils would you recommend?

If I'm smart I'll just wait until I inevitably put a bumper/winch on the front before I make any changes. But sometimes I just like to buy parts.

 

[Crikeymike]

Hey Mike,

I've been running 302/700 725/701 for about 3.5 years now. 2020 with KDSS. The rear tends to sag just slightly and I've considered going up a step in rear coils. Which coils would you recommend?

If I'm smart I'll just wait until I inevitably put a bumper/winch on the front before I make any changes. But sometimes I just like to buy parts.

Hey bud

The next step up in the rear from what you have now are the C59-327 coils.

Dobinsons C59-327 Rear Coils | Toyota 4Runner FJ Cruiser GX470 GX460

 

[osugsxr]

Reached out to mike regarding this as well, few questions for others with similar set up. Looking at the following at a decent price hopefully, goal is to keep a leveled ride and height about the same.

IMS adjustable; current setting is at 2" lift , would this need to be adjusted?

front coils c59-238 --- same height as current ride 21-21 1/2" at front hub
rear coils c59-323----1/2" gain in height vs stock now, I measured yesterday and think it was about 22-23" range hub to wheel well.


Questions
Will the following set up provide a leveled ride with little rake or similar to current set up of the FJ trd pro 6112 with 600lb springs?

 

[osugsxr]

Reached out to mike regarding this as well, few questions for others with similar set up. Looking at the following at a decent price hopefully, goal is to keep a leveled ride and height about the same.

IMS adjustable; current setting is at 2" lift , would this need to be adjusted?

front coils c59-238 --- same height as current ride 21-21 1/2" at front hub
rear coils c59-323----1/2" gain in height vs stock now, I measured yesterday and think it was about 22-23" range hub to wheel well.


Questions
Will the following set up provide a leveled ride with little rake or similar to current set up of the FJ trd pro 6112 with 600lb springs?

looks like ill need to adjust the front by .5-.75" to have a level ride.

 

[Crikeymike]

looks like ill need to adjust the front by .5-.75" to have a level ride.

To remove all the rake, the front has to be 2" more lift than the rear. Not ideal though if you ever load up the rear end with gear as you'll have reverse rake then

 

[osugsxr]

To remove all the rake, the front has to be 2" more lift than the rear. Not ideal though if you ever load up the rear end with gear as you'll have reverse rake then

yeah i dont want negative rake, just similar height to what I have now.

current heights
front 21-21 1/2" at front hub
rear 22-23" range hub to wheel well.

So Ill keep the rear about 1/2- 1" higher

 

[tpotnoc]

For reference I installed the FJ TRD Pro kit + daystar 1.25" perch spacer + OME 10mm spacer. Wanted to eliminate sag on heavy loads so I replaced my Wheeler T13 with the C59-327 rear springs and here's what the stance and measurements look like:

With Wheelers T13:

With C59-327:

Ground to fender measurement with Wheeler T13
FR - 36 4/16
FL - 36 4/16

RR - 38
RL - 37 15/16

Ground to fender measurement with C59-327
FR - 36 7/16
FL - 36 7/16

RR - 40
RL - 39 12/16


Sent from my iPhone using Tapatalk

Hey do you still have your truck with 327 coils in the rear? I’m in the process of going with the Dobinson setup by I for the life of me cannot decide between 325 and 327. How is the ride when the car is empty? Super stiff? Uncomfortable over bumps? How does it compare when you get fully loaded? What’s your experience?

 

[tpotnoc]

I swapped my C59-325 rear springs for 505s a week ago. I'd say it's perfect now, should've done it from the start. Luckily its not the most expensive mistake. Looks better and noticeably easier to get shit into the back. Ride is the same of course, same spring rate and shocks. Front is also the same (300s with 574 struts).

Before:

After:

Hey, these photos arent loaded anymore. Do you still have them handy? Hoping to see the difference.

 

[CrawlCulture]

[MENTION=148378]Crikeymike[/MENTION]

In your experience how much height would you gain going from the 329s to the 677Vs on a 5th gen 4runner? I am not really looking to gain much height in the back but there obviously isn't a 2" long travel option so I stepped down the weight hoping that they would be somewhere close. I have a rear bumper but it really only added 300lbs extra once you add up what we put on and subtract what we cut out

 

[Crikeymike]

[MENTION=148378]Crikeymike[/MENTION]

In your experience how much height would you gain going from the 329s to the 677Vs on a 5th gen 4runner? I am not really looking to gain much height in the back but there obviously isn't a 2" long travel option so I stepped down the weight hoping that they would be somewhere close. I have a rear bumper but it really only added 300lbs extra once you add up what we put on and subtract what we cut out

About 1". But it all depends on the total added weight.

300lbs of weight isn't much, but when it's hanging off the rear most end of the vehicle, it's leverage. 300lbs inside the cargo area is different on the suspension than 300lbs off the rear bumper, or 300lbs of tongue weight from a trailer.

 

[CrawlCulture]

About 1". But it all depends on the total added weight.

300lbs of weight isn't much, but when it's hanging off the rear most end of the vehicle, it's leverage. 300lbs inside the cargo area is different on the suspension than 300lbs off the rear bumper, or 300lbs of tongue weight from a trailer.

Alright, was hoping to get a little less than the full 1” since I was going from springs rated a max of 800lbs to ones with a max of 400 and an 18mm wire to a 16mm, but we’ll see. I feel like the 329s gave me a little more height over the 327s but I never really took any measurement so now I’m not as confident haha . There are always the 675vs if the 677s go too ass high. Thank you

 

[West Texas Bound]

[MENTION=148378]Crikeymike[/MENTION]

You set me up back in 2017 with my current Dobinson's suspension which is great but I'm looking to upgrade to MRA struts/shocks.

Up front I have C59-302s with about 160lbs of weight between bumper and winch. In the back I have C59-505s with stock weight. For shocks I have Bilstien 5100s at the lowest setting.

Currently my front end is a little lower than I want and my back is raked a little higher than I want. Do you recommend any spring changes while upgrading to MRA? I'm looking to get 2.5-3" in front and then level/no rake in back. I have airbags for any squatting while fully loaded.

 

[Crikeymike]

[MENTION=148378]Crikeymike[/MENTION]

You set me up back in 2017 with my current Dobinson's suspension which is great but I'm looking to upgrade to MRA struts/shocks.

Up front I have C59-302s with about 160lbs of weight between bumper and winch. In the back I have C59-505s with stock weight. For shocks I have Bilstien 5100s at the lowest setting.

Currently my front end is a little lower than I want and my back is raked a little higher than I want. Do you recommend any spring changes while upgrading to MRA? I'm looking to get 2.5-3" in front and then level/no rake in back. I have airbags for any squatting while fully loaded.

Hey bud

Yeah, you might need to go up to the C59-314 coils to support that extra weight and give you more lift.

In the rear, you don't need to change the springs unless you want to change the lift height.