Suspension Upgrade / Improving Ride Comfort

[clindsay123]

Howdy all,

I've been on a quest to sort out the rough ride of my 100 series since I purchased it 6 months ago and have read through many threads on mud to determine a solution. Unfortunately, I'm more confused than when I started. My initial attempt was to replace my aging 275/70/18 E rated K02s in hopes that moving to a 17" wheel w/ a C rated K02 would smooth out the ride. To my dismay there is little to no improvement even when lower to 33 PSI all around.

Additional context - it's a 2005 cruiser 185k miles and stock suspension. I've got a BIOR front + rear steel bumpers and a winch.
I did remove the 2nd and 3rd row seat. There are also rear airbags for towing from the PO.

From what I've read it could be helpful to:

1. Replace shocks / springs - perhaps the OEM shocks are not suitable for my added weight?
2. Replace bushings - in the following order of priority:
   -Body bushings
   -Front Anchor Arm Bushing & Stabilizer bushings
   -Rear Upper and Lower Control Arm & Stabilizer
   -Three (3) Front Differential bushings
   -Three (3) Engine mounts
3. Run a P Metric tire

PS. I plan on lifting the vehicle a about an 1-1.5 inches by cranking the torsion bars and getting new springs or using spacers in rear. Not sure if that will rule out using OEM shocks.

 

[Coin]

Are there clunks on rougher roads/bumps or just a harsh stiff ride? If no clunks then and If your ride is that rough carrying that much weight, then you probably don’t have stock springs.

Btw, body mounts are last thing to worry about replacing.

 

[2001LC]

The more tire sidewall plies, knobby and harder tread tire. Which are great for on the rocks off road. The stiffen the ride.

Having two set of wheels w/tires. One set with softer tires/less sidewall plies, for DD. Then swap on your Ko2's, for off road. Is one solution.

Once you load on the extra weight of iron bumpers, armor, etc. and lift (beefier coils & crank on T-bars). Even softer tires, won't take out all the rough ride. But helps.

If you really want a cushy ride. Get into LX470 or 06-07LC with AHC. Which is hydraulic suspension, with dial in comfort thru sport mode. It is so sweet and has lift on demanded. Can also be set up for added lift (sensor lift).

 

[clindsay123]

Are there clunks on rougher roads/bumps or just a harsh stiff ride? If no clunks then and If your ride is that rough carrying that much weight, then you probably don’t have stock springs.

Btw, body mounts are last thing to worry about replacing.

Hey Coin, the only clunk I've noticed is when going between reverse and drive. My issue is the ride is just rough, all of the potholes in Los Angeles blow up the vehicle and I can constantly feel any and all of the broken pavement. No issue on smooth roads.

Are you saying I don't currently have stock springs, or that I should replace the stock springs?

 

[clindsay123]

The more tire sidewall plies, knobby and harder tread tire. Which are great for on the rocks off road. The stiffen the ride.

Having two set of wheels w/tires. One set with softer tires/less sidewall plies, for DD. Then swap on your Ko2's, for off road. Is one solution.

Once you load on the extra weight of iron bumpers, armor, etc. and lift (beefier coils & crank on T-bars). Even softer tires, won't take out all the rough ride. But helps.

If you really want a cushy ride. Get into LX470 or 06-07LC with AHC. Which is hydraulic suspension, with dial in comfort thru sport mode. It is so sweet and has lift on demanded. Can also be set up for added lift (sensor lift).

My guess is the sidewall plies only tell part of the story. For example, my C rated Ko2s have 2 ply sidewall.
Most SL rated AT tires also have a 2 ply sidewall. Does that mean the SL sidewalls are just as durable as the Ko2s? Probably not... I would think the sidewall construction is the other part of the story and also explains why the C rated carcass can handle higher loads.

It also seems there are plenty of 100 owners who have added armor, lift, sliders and claim to enjoy a smooth ride.
I would probably target a 200 series before paying 06/07 100 series money, but agree that the AHC rigs I test drove felt fantastic.

 

[Live to Ski]

I bet your springs need a "refresh".

i have 2004 with then 120K miles. springs allowed the bump stops to limit travel. this would, of course, amplify any undesirable qualities due to age.

try bumping the tbars a tooth or so in front, springs re-arched in the back.

'course, probably cheaper to update suspension w. mild lift at this point.

 

[clindsay123]

I bet your springs need a "refresh".

i have 2004 with then 120K miles. springs allowed the bump stops to limit travel. this would, of course, amplify any undesirable qualities due to age.

try bumping the tbars a tooth or so in front, springs re-arched in the back.

'course, probably cheaper to update suspension w. mild lift at this point.

What lift would you recommend given my added weight from armor? Also I'm not familiar with re-arching springs. Is that something a shop can do?

 

[Bennymic]

What lift would you recommend given my added weight from armor? Also I'm not familiar with re-arching springs. Is that something a shop can do?

I just went from oem non ahc to a 2" dobinsons 3way mra and the ride quality is night and day better. Also gained about 4-5" of lift from I'm guessing the original 27 year old springs. Pretty sure we were riding around on the bumpstops. Wife is not happy since i told her it was only going to be 2". I set the high speed compression to almost the lowest damping and all the potholes etc have disappeared.

You choose the rear springs based on your added weight and just crank the torsion bars until you get the correct ride height.

 

[Trunk Monkey]

Not sure what you're comparing is against, it is a 3 ton truck after all.

 

[89BIGBLUE]

What lift would you recommend given my added weight from armor? Also I'm not familiar with re-arching springs. Is that something a shop can do?

I know you can have leaf springs re-arched, but I dunno about "re-tuning" coil springs.
Is this possible?
New coil springs for the 100 series are not crazy expensive or that difficult to replace, in my humble opinion.

 

[Coin]

Hey Coin, the only clunk I've noticed is when going between reverse and drive. My issue is the ride is just rough, all of the potholes in Los Angeles blow up the vehicle and I can constantly feel any and all of the broken pavement. No issue on smooth roads.

Are you saying I don't currently have stock springs, or that I should replace the stock springs?

Either your springs are short and you are hitting your bump stomps on every bump, or you have some very stiff aftermarket springs. Typically with more weight (front/rear bumpers) you will have a softer more wallowy ride, not a harsher one.

Check ball joints in the control arms too.

 

[GTV]

Steel bumpers and a winch on all stock (other than the airbags) original suspension?

You shouldn’t need coil spacers if you have airbags. How much pressure is in the rear bags?

Your original shocks are definitely cooked after 170k miles.

Take hub to fender measurements on all 4 corners. Crank the front bars up to stock height and pump up the airbags to match. Get new shocks. That may not make everything perfect but it’s a good starting point.

 

[Live to Ski]

me, myself, i had local small business cruiser head intall Trail Tailor 2 inch tuff dog coil springs (0-660#), shocks 53 mm fronts and 45mm adj rear. the adjustable rears seem to be key. Highwy.....firm 'em up, off-road....soften 'em down.

I recall (possibly in error) that tuff dog in no longer selling in usa.

 

[clindsay123]

Either your springs are short and you are hitting your bump stomps on every bump, or you have some very stiff aftermarket springs. Typically with more weight (front/rear bumpers) you will have a softer more wallowy ride, not a harsher one.

Check ball joints in the control arms too.

The ride oscillates from wallowy to harsh over bumps which makes me think I’m riding on my bump stops.

 

[clindsay123]

Steel bumpers and a winch on all stock (other than the airbags) original suspension?

You shouldn’t need coil spacers if you have airbags. How much pressure is in the rear bags?

Your original shocks are definitely cooked after 170k miles.

Take hub to fender measurements on all 4 corners. Crank the front bars up to stock height and pump up the airbags to match. Get new shocks. That may not make everything perfect but it’s a good starting point.

Do you happen to know the stock heights front and rear?

 

[vipergrhd]

I just went from oem non ahc to a 2" dobinsons 3way mra and the ride quality is night and day better. Also gained about 4-5" of lift from I'm guessing the original 27 year old springs. Pretty sure we were riding around on the bumpstops. Wife is not happy since i told her it was only going to be 2". I set the high speed compression to almost the lowest damping and all the potholes etc have disappeared.

You choose the rear springs based on your added weight and just crank the torsion bars until you get the correct ride height.

Could you post a few pics? would like to see a before and after if you have and under carriage shots.

 

[GTV]

Do you happen to know the stock heights front and rear?

 

[knuckle47]

I can’t say that this comment has any value to your issues and my only Toyotas in over 50 years have been FJ40’s and 45’s. Age has handicapped me to a point where I started to question the ride in my 1975 FJ40 as it was only a bang or hard hit with little compression or rebound from the suspension. Almost a deterrent to wanting to drive it… my bushings looked like strips of electrical tape hanging from the shackles. The bushings were changed and made a little difference.

I opted for the Terrain Tamer parabolic springs and shocks…the entire kit. Bushings, shackles, u-bolts..etc. When I removed the springs they looked like there was a substantial bind caused by age and rust. I needed to take them apart to remove the 4* caster shims. I needed to add them to the terrain tamer springs and the individual leafs from the front of the 40 were heavier in these spaces with rust and binding corrosion.

With the job finished, the truck rides substantially more smoothly, compresses and rebounds on potholes and washboard dirt road surfaces..it handles so much better my only conclusion has to be the 51 yr old stock suspension was at the root of the problem. It has gone from ‘would be nice to take a ride” to…‘I’ll be back later, I’m taking the Land Cruiser ‘

Hope this can be somewhat interesting to you

 

[DuckLN]

One notable nuggett - i’ve seen at least one tire manufacturer offer a c rated tire in the same tire as their E rated tire that both weighed the same. I assume this means they’re the same tire with diff letters and that because the C would exceed the “6 ply sidewall equivalent” there is no liability concern of warranty of fitness.

Even the michelins you can get these days are stiff riding compared to the michelins of 20 years ago. Its like the rubber has gotten harder.

 

[clindsay123]

Steel bumpers and a winch on all stock (other than the airbags) original suspension?

You shouldn’t need coil spacers if you have airbags. How much pressure is in the rear bags?

Your original shocks are definitely cooked after 170k miles.

Take hub to fender measurements on all 4 corners. Crank the front bars up to stock height and pump up the airbags to match. Get new shocks. That may not make everything perfect but it’s a good starting point.

do you know if it's possible to add spacers with airbags? I'd like to get an inch of lift to match the inch I'll be adding to the front end with the torsion bar crank.