What diameter shock absorbers better for KZJ78 - 2.0" or 2.5" ? (1 Viewer)

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Hi everyone,

I would like to talk about shock absorbers diameter, not suspension lift value.

Are there somebody who has an experience with mid-high range monotube shock absorbers on KZJ78 like King, Fox, Radflo, SAW, Bilstein and so on?

It is pretty hard to get good suspension play for "light" J7 series Land Cruiser Prado KZJ78. There are variety of "lift kit" options, most of them are crap and doesn't provide good ride quality in real world. Now I am deciding about custom order Fox or King remote reservoir shocks to improve ride quality. These shocks are tunable.

My driving distribution: highways 45...50%, gravel roads, country roads, roads without pavement 35...40%, light-medium off-road, some crawling 10...15%. I am planning one...two times a year to go to expedition for 2...4 weeks.

Vehicle weight in "local driving" state 2550 kg with driver and co-driver, estimated weight in "expedition" state 2800...2900 kg.

1) So there are dilemma - what shock diameter would be more appropriate to the driving circumstances described: 2.0" or 2.5"?
2) Which shock brand is better in terms of build quality, used material quality & longetivity - King Performance Series vs Fox Factory Racing series?
3) How often are you suffering from shock fade on your off-road Toyota?


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Hello,

Regarding your questions:
  1. I would go with 2.5 in.
  2. A good option for a KZJ78 is Dobinsons. Is it available in your country?
  3. Unless extreme off road and little maintenance -in that order- is your thing, fade is not really an issue.
I would go with a 2 in. lift and a medium setup.






Juan
 
Thanks @JuanJ for opinion. I am not sure that my question been understood correctly. So I have corrected a bit the initial text.
I am not talking about lift size. I would like to know about appropriate diameter of shock absorbers for KZJ78 in the context of driving style described before.

Furthermore I am talking about monotube shocks not twin-tube.

You are advising 2,5" size shocks and Dobinsons brand. But Dobinsons doesn't offer 2,5" bolt-on shocks for KZJ78, only classic twin-tubes which are the same crap as OME, Rancho's and so on. Exception is their MRR shocks which also not designed for KZJ78 and needs to be customized anyway.
 
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I wouldn’t worry too much about fade in a land cruiser unless you are really whooping on it at high speeds.

fox, king, icon make good 2.0/2.5s. If you are wanting to mid range or higher shocks, go for ones you can rebuild and easily revalve.
a good reseller or direct buy should be able to help you get the right valving For your weight and usage. It may take a few times to get it dialed in.
 
@FJBen I am afraid from fade when long driving washboard roads, steppe and so on. Yes, KZJ78 front axle has motion ratio close to 1:1 and requires less damping force than IFS. Rear shocks are installed under angle and it has significant motion ratio 1:0.87. Rear is heavier also, especially in expedition conditions. So rear need bigger shocks than front IMO.
I have experienced fade of OME Nitrocharger shocks on TLC120. 10...15 minutes of intense driving poor quality country roads and shocks start fading.
 
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I've worked in the Jeep 4x4 vehicle aftermarket for years, some of it under Fox. While not a Prado, they still use coils at all 4 corners so there are some parallels even though Jeeps are linked and not radius arm...

My first comment is that good suspension can really make a difference and you get what you pay for, but you just don't need race car parts unless you're a race car. Race car parts come with race car problems.

So, unless you're bombing through the desert at high speed, none of us "needs" 2.5s unless you weight 7000 lbs and are under sprung. A good 2.0 will do everything a 2.5 does performance wise, but obviously a 2.5" shock isn't working as hard at doing the same thing. That doesn't mean don't go with a 2.5 but if you have a budget and and you need to spread money around, spend money on the shocks you need and spend money upgrading the rest of the suspension to create a well rounded package. I'm a huge fan of upgraded bump stops, and I'd argue that something like that is more important than running a 2.5" shock. If you load up for big trips, go for compression adjustment. Try and maintain rubber or poly shock bushings, don't go with spherical joints.

On my Bj74, I was going to go with 2.5s, but they won't fit my front factory shock towers so I'm just not gonna worry about it and go with 2.0s. The OME shocks currently on the truck now are actually pretty damned great until you hit a washboard and are loaded up, then they lose their mojo and things get kind of tippy. It's actually fine, but I'm a snob having worked with suspension for so long, so I'm gonna get some remote 2.0s.

King, Fox and Icon are all good. King is probably the top notch, but they don't care about you because you aren't a race team. Their customer service is the worst in the entire industry unless you have their logo plastered on the side of your rig and compete professionally. Fox is fine, their high end consumer stuff is really good but they have supply chain issues and can't find their asses with two hands and a flashlight. Their valving is usually kinda wack so I'd be prepared to have their revalved once you've spent some time with the vehicle. IVD makes great consumer grade stuff, they have good customer service but their fill rates are fairly slow.
 
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Thanks for a great opinion @MyCruiserisaHogBeast

As I understood, the general meaning is follows: 2.0s are for vehicles until 5000 lbs weight, 2.5s zone is 5000 - 7500 lbs. My Prado weight is 5500...5600 lbs in "local driving style" and 6300 lbs and more in "expedition style".

I have read tons of forums and other sources about the topic 2.0" vs 2.5". Yes, 2.5s has more oil volume, more capable against fade, more durable etc. It is pretty clear.

There are people saying that 2.5s works more comfortable, better "eat" washboard and doing more comfortable on bigger bounces than 2.0s. Of course the performance of shocks depends on valving and pairing together with springs. It is clear also.

Many people in forums said that 2.5 provides significant improvement in terms of ride quality & comfort comparing with 2.0s. I have experience only with B46 series Bilsteins which are 2.0" classic emulsion monotubes with IFP.

One Ford Raptor owner's review: "I've had the 2.0's fade after driving on average desert roads with washboards, bumps and turns for 30-35 minutes at 25-35 MPH". Raptor weight is just bit more than my Prado. Ok, Prado has not IFS.

What is your experience with 2.5" shocks? What differences in ride quality could get from 2.5s comparing with 2.0" shocks?
 
P. S. My observations since I communicate with shock manufacturers and dealers. Almost every company on their sites are telling that "custom is everyday for us" and so on.

King - very good communication, provided some internal measurements I needed to be able to calculate min. possible compressed length;
Fox - no replied on e-mails at all;
Radflo - good communication until guy disappears when I did send them the custom measurements of shocks I need;
ADS - almost the same as Radflo. More than month has left from our conversation and I am still waiting for the estimate;
Icon - no reply neither e-mails nor contact form on website at all.

Very good communication is being with some tuners/dealers of Fox and King, but Filthy Motorsports. Ben replied on few emails and disappears when I tried to get approx. term of reply by matter on my request.
 
Thanks for a great opinion @MyCruiserisaHogBeast

As I understood, the general meaning is follows: 2.0s are for vehicles until 5000 lbs weight, 2.5s zone is 5000 - 7500 lbs. My Prado weight is 5500...5600 lbs in "local driving style" and 6300 lbs and more in "expedition style".

I have read tons of forums and other sources about the topic 2.0" vs 2.5". Yes, 2.5s has more oil volume, more capable against fade, more durable etc. It is pretty clear.

There are people saying that 2.5s works more comfortable, better "eat" washboard and doing more comfortable on bigger bounces than 2.0s. Of course the performance of shocks depends on valving and pairing together with springs. It is clear also.

Many people in forums said that 2.5 provides significant improvement in terms of ride quality & comfort comparing with 2.0s. I have experience only with B46 series Bilsteins which are 2.0" classic emulsion monotubes with IFP.

One Ford Raptor owner's review: "I've had the 2.0's fade after driving on average desert roads with washboards, bumps and turns for 30-35 minutes at 25-35 MPH". Raptor weight is just bit more than my Prado. Ok, Prado has not IFS.

What is your experience with 2.5" shocks? What differences in ride quality could get from 2.5s comparing with 2.0" shocks?

If you're getting shock fade from a good remote 2.0 that you wouldn't get from a 2.5 you're really pushing it. Raptor guys are a different breed, and if you're pushing a straight axle 4x4 that hard you should probably graduate to a race ready bypass coil over set up, and I generally try to steer people away from coil overs unless they need them. A 2.0 will support a heavy application if you aren't treating it like a trophy truck, but yeah a 2.5 is more durable simply because of increased fluid volumes and large components. If you're looking to have an Expedition style rig and you were my customer I would advise you to take a hard look at your priorities. The more custom and high performance you go away from the factory set up, the more problematic, harder to support and repair it becomes. A simple, smart suspension set up is the way to go for an expedition rig. Some big travel, fast rebound whoop eating mega suspension is AWESOME to drive, but wears out quickly and becomes a liability when you're away from civilization.

Again not saying don't go with 2.5s, just know what you're getting in to and work on creating a reliable, well rounded suspension.

During my time working in the suspension game, I found that a vehicle on 35s with limited wheel travel with gearing and lockers and a good driver will get anywhere a vehicle on 40s with massive race car wheel travel (assuming both vehicles are full bodied and the owners care about keeping them that way). It might do it more slowly and may not look as impressive for Instagram, but it'll get you there with less broken axles and control arms.
 
Yes, I fully agree with you about expedition circumstances and chances to get the bottle of nitrogen to refill the shocks in the middle of Africa would be pretty poor. Simple is better in the expedition style off-road. However I would try to go for 2.5s and test it on my own skin. I believe that 2.5s will perform better than 2.0s.

You said the shocks wears out quickly. Could you explain more detailed - why?
 
It sounds like you are set on 2.5 no matter the advice given. I’m not sure why but that’s ok. He’s given you every reason at why a 2.0 in your situation is easily adequate and will only be bad if you are seriously whooping on it, and at that level you are better off going custom suspension.
He said custom suspensions in general wear out much quicker than factory. In a full bodied rig you just don’t “need” high dollar custom suspensions.

I really like the air bump stop idea, could really help


again, the raptor and those people are a completely different breed from us lol.

good luck and keep us updated.
 
Simple is better in the expedition style off-road. However I would try to go for 2.5s and test it on my own skin. I believe that 2.5s will perform better than 2.0s.

Best to get shocks from someone who is local to you. If you custom order from the States, revalving, servicing or warranty is going to cost quite a bit.

Haven't tried the OME BP51 (2.0), but if you have $ to blow you will find OME dealers everywhere. You can also fine tune them to your needs alot easier without revalving. Tough Dog dealers are also everywhere.

Personally only met one person travelling internationally on 2.5's. Mostly jewelry otherwise. Don't know about you, but I sure wouldn't want $4k in shocks while travelling the Third World. I spray bombed my Fox 2.0 RR black and they were $1k. As others have said, there's better things to spend $ on
 
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@SHREDwagon The FOX Factory Racing series shocks has so simple design so to do some service is easy for almost everyone technically person. Yes, you are need to know oil viscosity to correctly choose oil to replace factory oil. Also you should have the nitrogen kit to refill them. All replacement parts you need could be order pretty easy. Shock dyno machine is available in the closest rally shop.

OME BP-51 would be great option but since they are position sensitive shocks there are almost not possible adapt them to standard shock mounts of KZJ78. Tough Dog not an option. TD's are twin-tube shocks the same as OME Nitrocharger, Dobinsons, Rancho and so on.

I already have set of OME Nitrocharger (60089 & 60090) and another set of Dobinsons (GS59-634 & GS59-633) shocks for my KZJ78. Both of them are not providing ride quality I would like to get.

OME gives excessive body roll, lack of rebound dampening and significant front dive when braking. Otherwise OME Nitrocharger are very good shocks in terms of build quality and longetivity. Dobinsons gives less body roll than OME, but they are harsh on washboard roads. They has lack of rebound dampening also.
 
@SHREDwagon The FOX Factory Racing series shocks has so simple design so to do some service is easy for almost everyone technically person. Yes, you are need to know oil viscosity to correctly choose oil to replace factory oil. Also you should have the nitrogen kit to refill them. All replacement parts you need could be order pretty easy. Shock dyno machine is available in the closest rally shop.

If you're willing invest $700 in tools to rebuild the shocks, by all means get the best you can afford. Having rebuilt 2.5's,recommend a decent vice with rotating jaws, urethane vice inserts, spanner wrench, seal pick, dual gauge regulator (FOX), piston plunger and a nitrogen bottle with hose. First one takes a while and you may destroy a teflon seal, so have spares.

I think you will be really happy with the 2.0 RR. The 2.5's are justified with increased unsprung weight (37's, beadlocks, etc). Or, to reduce body roll with sway bar removed (4 LO wheeling with RTT)

Unfortunately all these shocks are geared for racing and come with Urethane, not rubber bushings. My experience has been these are less durable long term.

Are dual rate coils available for the Prado? If so, this will help narrow down your shock choice.
 
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Yes, I fully agree with you about expedition circumstances and chances to get the bottle of nitrogen to refill the shocks in the middle of Africa would be pretty poor. Simple is better in the expedition style off-road. However I would try to go for 2.5s and test it on my own skin. I believe that 2.5s will perform better than 2.0s.

You said the shocks wears out quickly. Could you explain more detailed - why?

This is always something that gets guys who are stepping into a more extensive suspension build caught up. A lot of times the really high performance stuff is designed to survive extreme punishment but is not designed to survive longer milder situations in harsh conditions IE, salt, sand and water contamination, ect. Many use steel spherical joints instead of bushings. Great for wheel travel and racing, really bad for longevity. A lot of 2.5s sub heim joints for bushings, which will start clunking and popping after a few thousand miles. I can’t stand heim joints on anything that I’m going to spend more than a couple of hours at a time in.
 
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@SHREDwagon The FOX Factory Racing series shocks has so simple design so to do some service is easy for almost everyone technically person. Yes, you are need to know oil viscosity to correctly choose oil to replace factory oil. Also you should have the nitrogen kit to refill them. All replacement parts you need could be order pretty easy. Shock dyno machine is available in the closest rally shop.

OME BP-51 would be great option but since they are position sensitive shocks there are almost not possible adapt them to standard shock mounts of KZJ78. Tough Dog not an option. TD's are twin-tube shocks the same as OME Nitrocharger, Dobinsons, Rancho and so on.

I already have set of OME Nitrocharger (60089 & 60090) and another set of Dobinsons (GS59-634 & GS59-633) shocks for my KZJ78. Both of them are not providing ride quality I would like to get.

OME gives excessive body roll, lack of rebound dampening and significant front dive when braking. Otherwise OME Nitrocharger are very good shocks in terms of build quality and longetivity. Dobinsons gives less body roll than OME, but they are harsh on washboard roads. They has lack of rebound dampening also.

This is good advice. If you want to run a good 2.0 for a long adventure I might recommend picking up a high quality consumer grade 2.0 and picking up a spare of each. Rebuilding a shock is a pain in the ass unless you’re in a clean environment. I don’t think I would choose a 2.5 for this type of use.

I’ve also heard great things about BP-51s, although I don’t have any personal experience other than playing with them off the shelf and saying “wow these are pretty cool.” They seem to be a nice bridge between the race stuff and consumer grade stuff, might be something to look in to.
 
If you're willing invest $700 in tools to rebuild the shocks, by all means get the best you can afford. Having rebuilt 2.5's,recommend a decent vice with rotating jaws, urethane vice inserts, spanner wrench, seal pick, dual gauge regulator (FOX), piston plunger and a nitrogen bottle with hose. First one takes a while and you may destroy a teflon seal, so have spares.

I think you will be really happy with the 2.0 RR. The 2.5's are justified with increased unsprung weight (37's, beadlocks, etc). Or, to reduce body roll with sway bar removed (4 LO wheeling with RTT)

Unfortunately all these shocks are geared for racing and come with Urethane, not rubber bushings. My experience has been these are less durable long term.

Are dual rate coils available for the Prado? If so, this will help narrow down your shock choice.

I agree on the shocks. I don’t think the upside of a 2.5 is worth the money or the potential headache.

Good coils go a long way, I have no idea what the market is like for Prados but in Jeepland and for 80 series a good cool is the difference between a harsh suspension with broken components and something you can actually enjoy on a dirt road.

Polyurethane can beat out rubber if it’s high quality and properly preloaded and tightened. Rubber is nice because its easy and cheap and works really well on just about any suspension.
 
To pass front shock through coil support ring will be a bit painful. Otherwise I won't see any problems.

@SHREDwagon If I would choose 2.0s shocks I will need the same equipment to service them.
@MyCruiserisaHogBeast consumer grade 2.0" shocks are not serviceable. That means they cannot revalve.
 
To pass front shock through coil support ring will be a bit painful. Otherwise I won't see any problems.

@SHREDwagon If I would choose 2.0s shocks I will need the same equipment to service them.
@MyCruiserisaHogBeast consumer grade 2.0" shocks are not serviceable. That means they cannot revalve.

Correct, I would just get nice consumer grade stuff and bring spares.
 
I'm in the market myself for our HZJ79 and have pretty much settled on Terrain Tamer smart coils (dual stage) up front with their Pro adjustable RR shocks (rebuildable) and rear parabolics. They make a kit for the Prado as well which I think would be an ideal solution as you would then have matched shocks and coils. Having been down the road of re-valving shocks to match coil rates, I now prefer to avoid the headache. Thinking dual stage coils will give you the best bang per $ for washboard and wheeling. I have them on the 80 and would not go back to linear.

I like the idea of BP51's for availability and rebound adjustability, but OME does not offer dual stage coils or rear parabolics with shock valving to suit.
 
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