Suspension for an overweight Tacoma (2nd gen)?

[geophile]

I'm looking at getting a 2nd generation Tacoma with a Four Wheel Camper slide-in (~1,350 lbs. dry) and ARB steel bumper with a winch. I know that similar rigs are notoriously overweight, but seem to manage okay nonetheless. This one already has an added leaf spring (or maybe a whole replacement pack) from Boise Spring Works, so there's no sag in the rear, but I wasn't crazy about how it handled on a washboard gravel road when I took it for a test drive. So I'm thinking about how I can improve the suspension for both on and off-road travel with all that weight. Note that I have no plans to do any hard-core rock crawling, but a lot of the "roads" where I travel and camp are really more like rough ATV trails.

Option 1: Timbren active off-road bump stops
That would protect things from the current suspension bottoming out hard and probably improve handing in the bumps. It's also relatively inexpensive and trivial to install.

Option 2: New coil-over suspension
I like the looks of the Old Man Emu BP-51 suspension, but that would be an expensive upgrade and I'd only want to do it if it'll make a big difference. How well would you expect that to work with my overloaded taco on trails, washboard roads, and pavement?

Option 3: Something else?

 

[plainjaneFJC]

Is option 3 a different vehicle? I can’t imagine putting a 1350lb dry weight camper on that truck.

 

[dstefan]

I had a 09 Tacoma that I just loved. It was perfectly built out with Icons, Deaver springs, Timbrens, one size larger DuraTrac tires, aluminum front and lightweight steel rear bumpers, winch sliders, lightweight skids, etc. It went anywhere I pointed it. No camper, just a hard shell tonneau cover with an ARB fridge and dual batteries. Still 500 lbs under GVWR, BUT when loaded for camping I know it was a bit over, though not much.

Thing is it handled atrociously on the road when fully loaded and with my wife and me. The braking was borderline dangerous. Loaded, despite the heavier duty aftermarket Deavers, it still rode on the Timbrens. My front axle weight was only 25 lbs below the front axle limit, despite the front bumper being a lightweight aluminum weighing only 55 lbs. We drove very cautiously on the freeways!

The rig you’re describing will be far heavier when loaded than mine ever was. The 2nd gens with the elockers only had a 8’ diff, which was one of their weak points — research it. Also, the lack of rear disc brakes made them really poor at braking with a load.

I wanted a camper, but knew in the end I couldn’t do a FWC due to the weight. I went with a lightweight shell pop-up (Ovrlnd) and I STILL couldn’t make myself put it on the Tacoma, despite it weighing only 275 lbs for the mid size version. That’s over a 1,000 lb less than you’re looking at in terms of dry weight. Consider that camper, dry, is more than your published payload, without gear, water, your family, friends or dogs or you in the truck!

Sure, plenty of folks overload their Tacomas. And, it can work OK, but don’t fool yourself. That truck will be way overloaded and to make it handle as you want will take a lot of mods, and then you still will have weak axles, diffs, and all the other systems that aren’t engineered for that much weight over.

I’m not a weight nazi — my current Tundra is slightly over GVWR loaded up, but that’s largely due to mods to the truck suspension, etc to make it safer and more bullet proof, not to my camper shell that weighs 360 lbs. Most of the components are built more stoutly than the Tacomas, despite the poor payload rating. It has a 10.5” rear diff and 9.5” front — the rear is a slightly downrated diff from a 3/4 ton Toyota commercial vehicle. I know I’m not outside the engineering safety range on it, and I don’t even know the camper is there, but I’m still cautious about weight.

Do what you want, and if you get the rig, it’ll probably work out — Tacomas are pretty tough, but just know you can’t really compensate for that much weight without essentially rebuilding the truck. Look around for a first gen Tundra and used camper. Just saw one on here (just the truck) for $9K a few days ago. Or, go for older 3/4 ton if you want a big camper.

Just my 2 cents . . . good luck with whatever you do!

 

[tacollie]

Message @wicked1 . His taco is heavy and he has dealt with it and continued to enjoy the rig.

 

[Mickey Bitsko]

How many times have we seen this scenario..
Good luck..

 

[rruff]

Boise Spring usually does packs... if you are level with that load, I'm guessing you have a pack.

You don't mention shocks... what are they? If they are OEM or worn, I can recommend Ironman FCPros which I have on my Tundra and like. Much better control and offroad performance. Look for a 15-25% off sale which they have regularly. BP-51 are another level and cost much more... so they'd probably be great. One thing I like about the IMs though is that they have no gas charge and the seals seem to last longer than they do on the fancy shocks.

You didn't mention tires either, that's important as well.

If you still aren't happy with the handling with better shocks, we can talking about additional mods.

 

[97heavyweight]

I have a 3rd gen tacoma on BP-51s and it is amazing. My rig's full weight with passengers and gear is 6500lbs. So i am definitely in the overweight category. I'll definitely second the brakes are going to be borderline dangerous, but once you know that just keep your distance as best you can.

 

[MR E30]

I'll chime in with what I have experienced:

I am in the moderately overweight category, though certainly not in the 1,300 lb. dry category (that's too much IMO).

I went all out with my suspension. Fronts are Radflo 2.5" extended travel shocks with compression adjustment on the reservoir, custom valved for my weight and driving style. Springs were also chosen based on overall weight. Aftermarket bump stops and all of the other various front end modifications were done as well.

For the rears I went with custom Alcan leaf packs, manufactured for a 2" lift and 1,300 lb. capacity, again with my driving style in mind. These are progressive leafs, and I am 100% convinced these are the only way to go if you leave your camper on your truck permanently, as I do. They ride like a dream.

I cut things off of my frame at the rear and welded on AG relocated rear shock towers, and installed massive 12" 2.5" Radflo extended length rear shocks, again with compression adjustment on the reservoir, custom valved and tested for my exact truck.

Archive Garage hammer hangers with shackles and the cross brace as well. More aftermarket bumps, limit straps, etc.

Gears, armor, blah blah. All those things.

The truck drives like a dream. Sounds unlikely, but I can sometimes forget that it is even back there. The suspension does that good of a job.

These things cover the offroad portion mainly. Truck is no slouch, and goes where I tell it.

As far as brakes, I am on stock stuff. I have no braking issues. Remember, the interaction between your brake pads and rotors is not the limiting factor in your brakes performance. The interaction between the tire and ground is. And your ultimate stopping force is predicated on the normal force experienced between your tire and the ground, as the friction (experienced as a shear force between tire and road) is a function of that normal force (i.e. the harder you push down, the larger that shear force before slippage, the harder you can brake). Now, your pedal feel will change, especially if you need to brake aggressively, but I suggest doing what I did and practicing/experimenting a bit in a large, empty parking lot, to get used to the feel. You have to push considerably harder than you may realize.

If you are encountering a long, steep descent, use engine braking and stab off speed with your brakes when required. Do not ride your brakes the entirety of the descent, this is poor/improper driving practices, overloaded or not.

I, like many of you, am heavy. I modified my driving habits first and foremost. Extra space between other drivers on the road. Stick to those posted speeds (or even slower if no one is around) on sweeping corners. Drive slower overall (I stick with the speed limit as my max in town, and I stick with 67 mph as my max on freeways).

A slightly overloaded truck is quickly matched or outpaced by an empty Tacoma going just a handful of MPH faster.

Reducing speed, along with some of the benefits of the modified underside, cover the on road portion of driving.

For a truck as heavy as you are considering, you need Option 3, which is a lot closer to what I posted, if not even better. I would also look at frame reinforcements as well. The couple driving an Access cab Tacoma around the world had failure of their front bed mounts, causing their FWC to get dangerously close, or even touch, the top of their cab. The FWC has such an overhang over the cab that it really stresses those mounts. I resolved this issue with the relocated rear shock towers I mentioned, as the top of them tie into the bed itself, at the top of the wheel well, which does wonders for spreading the load from the camper back into the frame.

JD Fab makes bolt-in frame reinforcements for the back half of our trucks, which is now on my short list. With an FWC that is that heavy I would definitely get those as well.

Oh yeah; even with all of this there are still roads that are just nasty to ride on at almost any speed. Remember, if you want a smooth feel you need to reach a speed where your suspension just works itself, while your trucks COM stays 'flat'. When you go too slow your suspension has the ability to push the truck up, which makes it feel bumpy. You want the suspension to cycle itself up and down, while the truck stays flat. That's a 'smooth' ride.

There is an upper limit to the speed though, obviously. Even trucks with full LT in the front, 35's and 37's, with SUA in the rear, triple bypasses, etc. feel terrible on certain roads due to corrugations or whatever. It's an unfortunate reality.

 

[MotoDave]

Is option 3 a different vehicle? I can’t imagine putting a 1350lb dry weight camper on that truck.

This - I had a FWC Hawk in a Tundra and felt even that platform needed suspension upgrades (Add a leaf, air bags and shocks and Load Range E tires) to feel like it carried the weight well.

If I were set on a Tacoma i'd look at more minimalist campers like a Go Fast Camper.

 

[rruff]

As far as brakes, I am on stock stuff. I have no braking issues. Remember, the interaction between your brake pads and rotors is not the limiting factor in your brakes performance. The interaction between the tire and ground is.

That's true unless the brakes are marginal to start with and cannot generate the extra force needed to achieve a skid when you increase the weight. I'd guess that modern brakes have a good deal of margin where that is concerned. I'm thinking about a single panic stop from 80 mph, which should be worst case... not burning your brakes on mountain descents. Another factor is the diameter of the tire... but only if your brakes are the limiter rather than the tire-road friction.

Heavy trucks take longer to stop. The reason for this is that the coefficient of friction between the road and tire decreases as the normal force goes up. Changing the tire size has little effect on the contact patch directly, rather the tire pressure is the main thing determining this. Bigger tires will carry a given weight at lower pressure though, which should improve friction and reduce stopping distance. Tire compounds can also effect this of course.

For instance... C&D does braking tests in their reviews, Tacoma TRD Pro 70-0 in 180ft. F250 Tremor diesel takes 229ft. If the Tacoma was loaded to the same weight as the Tremor and given the same tires, I suspect it would do about the same. Like everyone who drives a heavy vehicle, you need to adjust your expectations and drive within your limits.

 

[calicamper]

Braking ability on heavy Tacoma’s is most definitely an issue that prior posters have direct experience with and the biggest reason other than lousy power and range they went to a bigger vehicle.

You add weight to any vehicle you increase the friction ie traction capacity of the tires. Add larger tires and every vehicle thats over loaded will reach a point the specced brakes no longer can apply the force needed to lock up tires. Add heat and brake force loss from heat and it just snow balls.

Stay light with the Toy truck or you’ll eventually realize you need a bigger platform be it inability to stop when you really need to or just expensive brake work more often than you/ your wallet prefers.

Yes stopping distance increases with weight but thats only part of the story.

 

[rruff]

Braking ability on heavy Tacoma’s is most definitely an issue that prior posters have direct experience with and the biggest reason other than lousy power and range they went to a bigger vehicle.

My guess is that the majority of anecdotal perceptions are inaccurate....

Toyota trucks seem to have more progressive brakes than what is typical. I know that when I get in another "newish" vehicle the brakes seem touchy. It's a modern trend I think, as the perception is that touchy brakes are better, stronger. What matters though is how the truck does in a panic stop from speed, which means you're mashing on the pedal, and the Toyotas do fine relative to similar trucks, meaning that the brakes are not the limiting factor.

Worst case, the Tacoma brakes are only strong enough to not be the limiting factor at GVWR. I don't want to give lawyers ideas, but I think if they were weaker than this, they'd be opening themselves to lawsuits. So say your severely overloaded Tacoma is 20% above GVWR, making your stopping deceleration rate .833 of the traction limit. You also put 10% larger diameter tires on which gives you a further detriment, yielding a .757 deceleration rate. That may seem bad, since your crappy brakes are only giving you 75.7% of the deceleration you could get with "perfect" (traction limited) brakes.

But as I said earlier, the stock Tacoma has a stopping distance from 70mph of 180 ft vs 229 ft for a stock F250 Tremor diesel... a .786 factor. I'd assume both are traction limited when unloaded, so this factor is due to weight. Maybe the F250 has great brakes and is traction limited with a load, unlike our hypothetical Tacoma which is hampered by weak brakes, but even with that, the difference is trivial due to the Tacoma's lighter weight. And don't even think about the 80,000 lb semi tailgating you which has a 2x longer stopping distance!

Frankly I think the "poor brakes" perception is pedal feel more than actual braking force. Regardless your stopping distance will be in the ballpark of other loaded pickups, and way better than a lot of heavier vehicles on the road. Know your limitations and drive accordingly.

 

[bkg]

My guess is that the majority of anecdotal perceptions are inaccurate....

Toyota trucks seem to have more progressive brakes than what is typical. I know that when I get in another "newish" vehicle the brakes seem touchy. It's a modern trend I think, as the perception is that touchy brakes are better, stronger. What matters though is how the truck does in a panic stop from speed, which means you're mashing on the pedal, and the Toyotas do fine relative to similar trucks, meaning that the brakes are not the limiting factor.

Worst case, the Tacoma brakes are only strong enough to not be the limiting factor at GVWR. I don't want to give lawyers ideas, but I think if they were weaker than this, they'd be opening themselves to lawsuits. So say your severely overloaded Tacoma is 20% above GVWR, making your stopping deceleration rate .833 of the traction limit. You also put 10% larger diameter tires on which gives you a further detriment, yielding a .757 deceleration rate. That may seem bad, since your crappy brakes are only giving you 75.7% of the deceleration you could get with "perfect" (traction limited) brakes.

But as I said earlier, the stock Tacoma has a stopping distance from 70mph of 180 ft vs 229 ft for a stock F250 Tremor diesel... a .786 factor. I'd assume both are traction limited when unloaded, so this factor is due to weight. Maybe the F250 has great brakes and is traction limited with a load, unlike our hypothetical Tacoma which is hampered by weak brakes, but even with that, the difference is trivial due to the Tacoma's lighter weight. And don't even think about the 80,000 lb semi tailgating you which has a 2x longer stopping distance!

Frankly I think the "poor brakes" perception is pedal feel more than actual braking force. Regardless your stopping distance will be in the ballpark of other loaded pickups, and way better than a lot of heavier vehicles on the road. Know your limitations and drive accordingly.

horrible comparison, IMHO, to use the Tremor. Tremor weighs over 8k lbs... nearly 2x as much as the tacoma. Load the tacoma up to 8k lbs and redo your math.

I own a Tremor and 2 tacoma's... there's no comparison in braking capability.

 

[rruff]

The Tremor is just an example of a 3/4 ton that everyone would deem suitable for that load. If the Tremor takes as long to stop as the Tacoma while both are carrying the same load, then the idea that Tacoma brakes are inadequate when you overload it, doesn't have merit.

I was quoting C&Ds braking tests of both these trucks... they differ from your perception that "there is no comparison in braking capability"... unless you meant the Tacoma is better.

 

[bkg]

The Tremor is just an example of a 3/4 ton that everyone would deem suitable for that load. If the Tremor takes as long to stop as the Tacoma while both are carrying the same load, then the idea that Tacoma brakes are inadequate when you overload it, doesn't have merit.

I was quoting C&Ds braking tests of both these trucks... they differ from your perception that "there is no comparison in braking capability"... unless you meant the Tacoma is better.

You're comparing a truck that weighs 1/2 as much as the other and claiming the brakes on the lighter truck are better. Put the same load in the tacoma and report back.