Scott B.'s 2015 Tacoma AC Build - Expo Style

Very nice! Please update us as you get some wear on them. My 4th gen 4runner eats front brakes too (same suspension brakes etc, except I have the larger sport/Tundra calipers) I have been happy with my last centric rotors and serve duty pads (I'm spacing on the mfg for them hawk?)

Your updates look nice! Bed them in well!
 
The clevis plate is 3/8". The piece of steel mounting the bumper to the frame (on each side) is the same piece that extends out forming the clevis.

I would have preferred a thicker piece (like I used on my Ranger bumper) but I think the 3/8" will be plenty strong. There is also a receiver hitch behind the tag, which ties both sides together. I think if I needed a really strong attachment point, I could use it - with a strong enough cross pin, of course.

I am late to this, but I would think 3/8" tie in is fine. The frame that you are bolting to is nowhere near 3/8. The frame would break first. I have seen 2 heavy duty bumpers ripped from jeeps. It was the frame that failed both times.
 
I am late to this, but I would think 3/8" tie in is fine. The frame that you are bolting to is nowhere near 3/8. The frame would break first. I have seen 2 heavy duty bumpers ripped from jeeps. It was the frame that failed both times.

I have been wondering if I should re-enforce the rear part of the frame.

I've seen some where the C-channel was boxed, and cross braces were welded in side-to-side.

Of course, then all your flex is concentrated at the front of the boxed in area, instead of spread across the length of the rear frame.

Since I'm not racing in the desert, I should probably leave well enough alone...
 
Dual Batteries, Part 1

My original - pre truck - plan included dual batteries. I planned on setting up a system similar to the one I had in my Ranger. Along the way, I had many conversations about dual batteries, and read many write ups on both single and dual batteries. There are different viewpoints out there, all of them backed with valid ideas. There is no wrong solution - only different.

I evaluated my intended use of the truck, and added in my many years of experiences of failed batteries. I compared different setup ideas, mapped to my experiences, and decided to run duals. Multiple batteries makes the most sense to me, redundancy being a good think.

The next big question is which battery(s) to run? And what size? Stock, the truck came with a Group 27 battery. I want to run AGM batteries, and heavy duty ones at that. I decided on Odyssey batteries, their Extreme series. So what size? They don't make a Group 27 size. The options are Group 31 and Group 34. G31 is quite a bit larger, and G34 is a little smaller. I decided on two G34 batteries. A G34 is 28 pounds lighter than a G31, and 2 G34s have more power than a single G31. The big thing is getting weight off the front suspension. The second battery is going in the bed. Future plans call for heavier front springs, so any weight reduction is a good thing.

I have never cared for factory style battery hold downs (j-bolts) and wanted a cage for the batteries. I found a nice cage by Artec - steel and not too expensive. I had them powder coated black, so they should last a long time.

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Installation was very straightforward.

Starting here -

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Battery removed -

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I drilled 4 holes for the mounting screws, and painted them to help prevent rust -

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Cage installed -

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The end result -

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As of yet, I have not changed any of the factory wiring. That will come with I install the second battery.
 
Looking good Scott. I have been looking for a reasonable priced hold down for an Odyssey battery and that one looks like a winner. Where did you get the powder coated version?
 
Looking good Scott. I have been looking for a reasonable priced hold down for an Odyssey battery and that one looks like a winner. Where did you get the powder coated version?

Thanks.

I ordered the cage from Summit Racing, it came as raw steel. Then I took it to a local powder coat shop. I have never seen one of these cages sold powder coated.

Which is too bad - it would have been cheaper!
 
Just curious here, and not trying to sound too horrible, but how does two G34's have more power than a single G31 when they're isolated from each other?
 
Just curious here, and not trying to sound too horrible, but how does two G34's have more power than a single G31 when they're isolated from each other?

Not when they are isolated - I meant when they are tied together.

I am going to use an ACR (as opposed to the 12V charger) to tie the batteries together.

I understand your idea of using the charger, and I think it is a good way to go. However, in my mind, the main idea behind dual batteries is to run the truck - accessories are secondary. I want to be able to start and run the truck from the second battery (I have had to do this once out in the woods.)

I probably should have been more clear in my post, but it was late and I was tired. ;)
 
I think you're missing my point.

The only time an ACR has the batteries paired is when your engine is running, and your alternator is charging them. Which is when an auxiliary battery bank is LEAST NEEDED. (A DC to DC charger is never useful in this case because the batteries are never paired - it sort of becomes an auxiliary alternator for your auxiliary battery). The point of the ACR is to keep the batteries separated when there is no charge voltage, thus protecting the front battery from being drained by auxiliary loads.

So, with my single 100AH Group 31 battery, I have more reserve capacity than your single 60-68AH Group 34 that is never paired with your front battery while in use.

I wrangled with this question myself when I chose how to build my 4Runner. And I chose to go with one single large Group 31 battery in the stock location, and augment my setup with solar.

All I care about is getting my fridge through the night, and a couple camp lights before we turn in. So... How am I going to charge my battery to carry the load through the night?
Either A) I've been driving all day, I arrive in camp late afternoon/early evening, and my battery is topped off from my alternator
or B) I've been sitting in the same spot all day, or arrived in camp early afternoon, in which case my solar panel is set up and kept pointed at the sun until sunset.

1) Solar is cheaper than a dual battery
2) Design is simpler than dual battery

And even if I did have a dual battery, guess what I'm still setting up during the day? Right!, my solar panel. Just because my battery is capable of running my fridge for 2-3 days doesn't mean I should put it through that much abuse, so again the logic pointed to a single battery design.

Further, most dual battery setups that aren't properly maintained never see a full charge put into them. For example, let's say I...
Went camping, ran fridge all weekend with minimal driving, battery amp hour capacity dropped to 40%.
Next week I drove 15 minutes each way to work and back for 5 days, battery amp hour capacity made it back up to 75%.
Went camping again the following weekend, ran fridge all weekend, minimal driving, capacity dropped to 15%
Charging while driving the next week only got it back up to 50% now..

See the trend here? The numbers are rough and slightly exaggerated, but it shows that without putting the auxiliary battery on some sort of charger when it's sitting, it never gets refilled, because our standard alternators aren't built for it, and the only thing that can recharge capacity is time. I don't care how many volts and amps you throw at a battery, the only thing that refills amp hour capacity is absorption of that energy over time.

With my solar, I'm putting more amps into the battery than the fridge/other items are taking out all day long, so the battery is just being topped off by the solar all day, until night when charging will cease. And when the sun rises, what little bit was used during the night just gets put right back in by the solar.

Just to give some levity, ONLY 3 amps of draw (fridge + a USB charger for a while + some LED camp lights for a couple hours) for a 24 HOUR period would require a 112AH@20 Hours rated battery.
 
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I think you're missing my point.

I more or less understood what you were saying, and this post does clarify your design.

The only time an ACR has the batteries paired is when your engine is running, and your alternator is charging them. Which is when an auxiliary battery bank is LEAST NEEDED. (A DC to DC charger is never useful in this case because the batteries are never paired - it sort of becomes an auxiliary alternator for your auxiliary battery). The point of the ACR is to keep the batteries separated when there is no charge voltage, thus protecting the front battery from being drained by auxiliary loads.

So, with my single 100AH Group 31 battery, I have more reserve capacity than your single 60-68AH Group 34 that is never paired with your front battery while in use.

Yes and yes. But, when I pair 2 Group 34s, I will have more reserve capacity than a single Group 31. Don't forget, I can switch the batteries to be paired when I need them.

All I care about is getting my fridge through the night, and a couple camp lights before we turn in. So... How am I going to charge my battery to carry the load through the night?
Either A) I've been driving all day, I arrive in camp late afternoon/early evening, and my battery is topped off from my alternator
or B) I've been sitting in the same spot all day, or arrived in camp early afternoon, in which case my solar panel is set up and kept pointed at the sun until sunset.

While keeping my fridge cold all night is important, it is not the primary reason I am going with dual batteries.

Further, most dual battery setups that aren't properly maintained never see a full charge put into them. For example, let's say I...
Went camping, ran fridge all weekend with minimal driving, battery amp hour capacity dropped to 40%.
Next week I drove 15 minutes each way to work and back for 5 days, battery amp hour capacity made it back up to 75%.
Went camping again the following weekend, ran fridge all weekend, minimal driving, capacity dropped to 15%
Charging while driving the next week only got it back up to 50% now..

I assumed both batteries would charge up faster than you have indicated. I think I made a bad assumption...

See the trend here? The numbers are rough and slightly exaggerated, but it shows that without putting the auxiliary battery on some sort of charger when it's sitting, it never gets refilled, because our standard alternators aren't built for it, and the only thing that can recharge capacity is time. I don't care how many volts and amps you throw at a battery, the only thing that refills amp hour capacity is absorption of that energy over time.

With my solar, I'm putting more amps into the battery than the fridge/other items are taking out all day long, so the battery is just being topped off by the solar all day, until night when charging will cease. And when the sun rises, what little bit was used during the night just gets put right back in by the solar.

Just to give some levity, ONLY 3 amps of draw (fridge + a USB charger for a while + some LED camp lights for a couple hours) for a 24 HOUR period would require a 112AH@20 Hours rated battery.

Remember, the primary reason I want dual batteries is to be able to start and run the truck if the main battery fails. Over the years, I have had 2 batteries fail when I was out - once in the desert, once in the woods. The first time, I was with another truck, and was able to get a jump start (before fuel injection and computers.) The second time, I just switched the batteries together (after disconnected the main battery from the system) and ran off the secondary battery. Redundancy leads to self reliance.

Perhaps, though, I may also add solar...
 
For that, I carry an inexpensive Lithium Jump pack. Mine is made by Anti-Gravity. So far I've only ever needed it for people who needed a jump, never myself.
 
Air Springs

The rear suspension of this truck includes heavy-load bearing Deaver springs, to accommodate the shell and interior, and all the stuff I normally carry in the truck. There is a little extra in the springs to accommodate the teardrop, yielding minimal sag.

However, when loaded for a multi-week trek, with trailer, extra fuel, water, food, etc., the rear end sagged more than I preferred.

I have known about air springs for many years, but never thought them the right solution for my use - which includes off-road travel. As it turns out, three of the trucks that usually accompany us on our westward travels run air springs. Their vehicle use is very similar to mine.

That knowledge set me to re-thinking my situation.

A big negative factor to me was the limiting of downward travel of the rear axle. My research led me to Daystar Cradles, which allow the bottom of the air spring to freely separate from the axle, allowing full suspension droop. Firestone specifically says not to use them. Without the cradles, the air springs would not fit (work) within my design parameters. I have read about many successful uses of the cradles out there, so I figured I would try them also.

The air spring kit, designed for a Tacoma.

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These are the bottom mounting brackets. They normally mount the bottom of the air spring, but instead will carry the cradle.

There is one more issue with these. Stock Tacomas mount the u-bolts with the nuts down - I have a u-bolt flip, with the nuts up. These brackets need to be modified to clear the u-bolt nuts.

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The cradles.

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Modified brackets to the right, the spacer blocks and vertical support plates I made.

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The spacer blocks will sit like this, on the bottom of the Firestone bracket. The lighter color on the bracket is where I sandblasted off the finish for welding.

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A mock-up of the pieces.

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Welded and painted.

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I got a new set of 5/8" u-bolts from RuffStuff. U-bolts are a one-time use fastner.

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Here we go. What I started with:

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The lower bracket with the cradle mounted.

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A view showing the vertical support sitting on the axle.

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I ran the air lines (red) inside fuel hose, for added protection.

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The finished product. The upper mounting bracket and air spring are mounting just as Firestone specified, so I did not include that here.

The red lines behind the shock are extended brake lines.

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I finished the installation right before my multi-week trip to California in September, and the springs worked very well. No issues or problems.

So far, I am very pleased with this mod.
 
Nice! That is a clever solution for the u-bolt flip scenario. The Firestone airbags and Daystar cradles have been one of the best mods on our Tacoma.
 
Bed Braces

Reading through the forums, (which is never good for the wallet!!) many people have found the sides of their truck beds splaying or spreading under load - bed rack, shell, etc. This problem is not limited to our composite bed trucks - full steel beds have been known to as well.

My truck bed did not exhibit much of a problem, but seeing as I have a shell, and go off road, I thought it better to be safe.

There are several companies that build braces for our trucks. Aside from the cost, none of the ones on the market will fit in my bed with the sleeping platform, without doing some modifications. Not only that, I have a welder. So, I decided to build a set myself.

A few minutes of figuring, and I came up with a workable design. By keeping the cross brace somewhat short, I won't have to modify the platform. Even short, it should be long enough to get the job done.

To get started, I bent and drilled some 3/16" steel:

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I cut some 1/4" steel for the cross braces. And, made some really ugly welds...

I was having some problems seeing, but got sufficient penetration. Strong, but ugly.

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Fortunately, the paint does a good job of hiding the mess.

I had some leftover ARP bolts from my 5.0L engine project, which dressed up this project nicely. Along the bottom, I used the factory bed bolts.

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Here, you can see the cross brace stops just under the platform.

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Assuming the welds hold, the bed sides should never splay.
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Oil Pressure

I guess you can say I am somewhat old school. I always like to monitor what is going on in the engine - with analog gauges. I have always been leery of "idiot lights".

When I added the transmission temperature gauge, I also added an oil pressure gauge. I finally got around to installing the sender. To be fair, one reason it took a while to figure out how to mount the sender was the location of the factory oil pressure sensor. I wanted to tap into that port, but doing so would interfere with an upcoming mod. More on that later.

I found this adapter plate made by GlowShift.

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It installs between the oil filter and the engine.

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The filter mounts on top of the adapter, as normal.

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This turned out to be a very simple solution to the problem - much simpler than I was originally thinking about.

So far, it works well, and does not leak.

And, it gives peace of mind knowing/watching the oil pressure.
 
Oil Pressure

I guess you can say I am somewhat old school. I always like to monitor what is going on in the engine - with analog gauges. I have always been leery of "idiot lights".

I'm a big fan of knowing what's going on in that mysterious engine bay as well and your addition of the oil pressure gauge reminded me of my Ford Ranger days. I forget the year...early 90's sometime...Ford changed up the instrument cluster in the Ranger and in doing so had a very accurate oil pressure gauge. The problem was that the oil pressure fluctuated when the vehicle was idling vs when the engine was under load. This caused the oil pressure gauge to move around quite a bit...still within acceptable ranges and perfectly normal, but it moved. The story goes that people began bringing their Rangers back to dealerships complaining that there was an oil pressure problem. It got so bad that Ford altered the clusters on future Rangers (by adding a resistor to the cluster and changing out the pressure sending unit) so that it firmly parked the pressure needle right in the middle of the gauge if there was any amount of pressure at all (above 5psi if I remember correctly). This effectively turned the oil pressure gauge into an idiot light.

Internet cowboys of the time figured out what models of sending unit would replace the Ford one and then would jumper over the resistor to reactivate the gauge.
 
I'm a big fan of knowing what's going on in that mysterious engine bay as well and your addition of the oil pressure gauge reminded me of my Ford Ranger days. I forget the year...early 90's sometime...Ford changed up the instrument cluster in the Ranger and in doing so had a very accurate oil pressure gauge. The problem was that the oil pressure fluctuated when the vehicle was idling vs when the engine was under load. This caused the oil pressure gauge to move around quite a bit...still within acceptable ranges and perfectly normal, but it moved. The story goes that people began bringing their Rangers back to dealerships complaining that there was an oil pressure problem. It got so bad that Ford altered the clusters on future Rangers (by adding a resistor to the cluster and changing out the pressure sending unit) so that it firmly parked the pressure needle right in the middle of the gauge if there was any amount of pressure at all (above 5psi if I remember correctly). This effectively turned the oil pressure gauge into an idiot light.

Internet cowboys of the time figured out what models of sending unit would replace the Ford one and then would jumper over the resistor to reactivate the gauge.

My '93 Ranger was one of the ones that had the 3 stage "idiot light" gauge.

And yes, I was one of the cowboys that replaced the shunt (resistor) on the back of the instrument panel with a wire, and changed the sending unit. o_O
 
My '93 Ranger was one of the ones that had the 3 stage "idiot light" gauge.

And yes, I was one of the cowboys that replaced the shunt (resistor) on the back of the instrument panel with a wire, and changed the sending unit. o_O
Oh please... let's not try to romanticize this. It's NERD, okay?

There's nothing wrong with being a NERD, you engineer, you. :rofl

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