Tacoma Loose Bed design Flaw explanation

Just out of curiosity, would it work better to shave off the molded part under the bed and place an appropriately sized polyurethane spacer in there?

I'm out of the country at the moment so I can't run outside and look at how it's actually designed.

 

I was thinking a stiff poly bushing from energy suspension.
I'll have to look into this.

 

I drilled some holes in my bed last night and I happened to notice that the Tacoma bed is not symmetrically shaped on my DCSB. There is an additional frame rest perch / support on the drivers side bed at the forward position and just behind the bed bolt. If you look in the wheel well, and get eye-level with the bed bolt you'll see what I'm talking about. The passenger side has no such feature. It was not apparent to me why.

This could be an explanation for why the passenger side seems to wear out first?

 

I just discovered this problem on my '13 Tacoma DCSB. Tried to take the bolt off and stripped the torx head, as the bolt threads were pretty rusty. Had to grind my bolt head into a socket shape and then bang a socket head on to remove it. Put a new bolt in, and luckily the frame threads were not stripped. It was seized on pretty good. I cut a piece of HD rubber and stuck it between the frame and the box. Seems work so far.

 

Glad you folks understand this problem.

 

I did not read what others may have suggested but I think that spot is getting weak due to the weights you have added. It's a design flow in my opinion because Yoda should have reinforced those spots where the bed is bolted to the frames. Yellow circle is the area where the weak spot of the bed is.

I think your solution to this problem may have to be different than simply grinding that thing down further. You may have to use a sheet metal or something that is strong enough and drill a hole through to reinforce the bed further to the front and back and bolt it to the bed. Here's a pic of your bed with blue (chicken scratches) to illustrate what I'm saying.

 

I think you missed my point!! There is no weak spot in the structure of the bed. The issue is under where the bed support rest on the frame ..flexing causes wear and the bed drops down on the sleeve. The bolt and sleeve remains tight but the bed becomes loose. The solution is to eleminate the wear between the composite bed and frame...an no I didn't grind anything!!

 

You actually have to stop the friction between the composite bed and the metal. A thin piece of conveyor belt will solve the problem for good.. Hope the washer dosnt eat into the composite bed with flex!!

 

I had a bed creak that was driving me crazy, going through everything trying to figure out what was rubbing, loose, rattling or otherwise. I thought my topper was creaking on the bed rails, a wiring harness clip, something under the rear storage, none of it.

I finally got someone to rock the truck while I was underneath and localized it to the bed mounts. I noticed that when I sprayed the mounts with WD40 it was finally quiet.

For a day.



So I ended up making something to reduce the noise. Ended up using standard UHMW, McMaster sells 1/16" thick sheets of impact-resistant UHMW in increments of 6"x6". I bought a 12"x12" and had more than enough. I ended up making 2.5"x2.5" square washers with a 1/2" hole in the middle but if you make 2"x2" squares you could get away with a 6"x6" sheet. You need a total of 6, although really only the 4 main mounts in the front and middle seem critical from a noise and wear standpoint. I did 6 so the whole bed raised equally.

There were other options for UHMW, fiber reinforced, oil-impregnated, high temp, mildew-resistant that all had some quality that I thought might be nice but they were only available in 1/8", 1/2" or other thicknesses that I thought might be too much. Plus they varied from a little more to a lot more in cost. The sheet I bought was $7, shipping would have probably been just as much, but I couldn't say I ordered a few things I needed.

UHMW I used: http://www.mcmaster.com/#8752k121



The left side middle, aft of the gas tank.


It's been quiet for a while now, no hint of creak any more and no need to spray up under there. It's only been this way for about a month, so can't say long term wear or resistance to road chemicals. I doubt UHMW is going to care about salts or typical oils, though I don't know about brake fluid.

 

Another photo, this is the right side front most. You can see the square shape is not perfect but I just did a quick and dirty fab. I can't tell a difference in body lines with 1/16" washers, but I don't have a very critical eye.

 

Great.. Understanding the issue is the solution to the problem!!!

 

Is the sleeve still sitting between bolt head and the frame?

 

The sleeve would be sitting on the UHMW washer, but it's still under the bolt head.

 

Great idea.

 

Well done Dave! Great contribution! . Thanks

 

Oh ok.

 

Dave's fix looked best to me (thankyou Dave!), so I ordered some 1/8" black UHMW from "popdisplays" on Ebay ($10), cut out a couple of 2"x2" pieces, and drilled 1/2" holes (3/8" is too small), and used them as a washer under the bolt head (on top) and as a spacer between the bed and the frame (underneath). The UHMW is high strength but flexible, corrosion resistant, and self lubricating, which seems like the right fit for this purpose.

The bed bolts are a PITA to remove- even after backing it out an inch, I was still using a breaker bar and probably 100 ft-lbs of torque, moving the bolt 1/4 turn at a time... at maybe 40 turns per inch, and several inches of bolt, that's a lot of work (I don't have an air wrench). Pissed me off. I *guarantee* that this bolt is not backing out by itself, as some have thought. I used a 3/8" drive T55 from a Neiko Torx set, available for $15-$20 from Ebay or Amazon- it seems to be a good quality set that includes sizes for the other smaller Tacoma bed bolts (tie-downs and rail headers).

I'm interested in hearing from others whether this fix will hold up over time. I'm assuming it will hold for a while, but thinking I will have to re-torque occasionally as the UHMW shims wear. I'm hoping that the self lubricating nature of the UHMW shims will reduce wear, and reduce or eliminate and wear on the bed itself, but since the plastic bed is clearly moving relative to the steel frame, some wear & tear is inevitable. I'd much rather need to replace the UHMW bushings, than the bed...

This is clearly a Toyota design fault, distressing to me as I have depended upon superb Toyota design for 40yrs. Attached is the evidence- a photo of my bed bolt backed out by an inch or two. You can see that the bolt hole & bushing is much larger than the diameter of the hold down bolt, a clear sign that the engineers *knew* that the bed would move relative to the frame mounting points. If the plastic bed moves relative to the frame, then there *will* be destructive friction wear at the point of motion between the frame and the plastic bed, and also between the plastic bed and the hold down bolt. This could not have escaped the engineers detection- they clearly sacrificed vehicle longevity for a quick fix that would last for a few years at best.

In my case, I started hearing "thunks" from the bed about 4 years after my new vehicle purchase. I roughly measured the distance between the hold down bolt head and the bed last week, by inserting a CDROM (0.050" thick)- it slid under the bolt washer easily, so my bed had worn down, at the bolt head, by at least 0.050" in 4 years (under 25,000 miles).

I think this bed to frame motion & wear may be due to frame/bed flexure, or perhaps to differential heat expansion on the bed & frame- in Hawaii, my plastic bed gets quite hot in the sun, while the frame (shaded by the bed) stays relatively cool. I also have one mile of very uneven dirt road between pavement and my home, so frame flexure is possible as a contributing factor.

In either case, this is an engineering failure, that should be covered by warantee, and should be corrected in future designs. I'm wondering whether 3rd Gen Tacomas are still experiencing this failure?

Note: to estimate the number of Tacoma owners affected by this problem, consider:

If:
X = the number of 2nd Gen Tacoma owners that actually write posts to TacomaWorld
Y = the number of posts about this particular problem (same bed bolt)
Z = the total number of Tacoma owners in the US

Then I think we can assume that the total number of Tacoma owners experiencing this problem (P) must be larger than:

P > Y*Z/X

Since Z/X (the total number of Tacoma owners, divided by the number of owners writing posts to this site) is probably a very large number (>10,000?), and since since at least 10-20 people have reported this problem on TacomaWorld already (this particular bed bolt, nearest the passenger seat), I would have to assume that this problem has already been experienced by 100,000 or more Tacoma owners.... is that significant? Should Toyota be notified?

PS: Please post, if you know the Toyota part # for this Torx bed holddown bolt- I'd be interested in purchasing replacements... I managed to scuff the torx edges when my breaker bar slipped during this work.

joel.

 

@joel.hawaii Bed bolts are part number 64189-0C011

 

I don't know if it's a design failure. Using a composite bed like this does solve the issue of dents and rust inside the bed, which has plagued all pickups forever. So I'll give Toyota the benefit that they may be trying to solve an issue. It's also lighter (gotta hit EPA and MPG numbers!) and cheaper. Things are moving towards pickups and cab-on-frame SUVs being legislated out of existence despite being popular with people so manufacturers are going to have to find solutions to keep meeting market demand for trucks.

But @joel.hawaii is right that it introduces a whole new dynamic with more materials interfacing through vibration, temperatures, etc. From what I see the main wear concern is under the bed between the frame and bed mount, which is why I put the UHMW sliding pads there instead of under the bolt heads, although both spots are probably eventually going wear. Now about 3 months in everything is still quiet, don't even think about it anymore.

One thing about getting those bolts out. It helps to climb under and clean the threads before removing them. There is a lot of exposed bolt below the nut. When this fills up with debris and rust you're cleaning it by trying to squeeze it through the nut, which ends up being a lot of work and potentially leading to stripped threads. Spraying them with penetrating oil and hitting them with a wire brush or wire wheel is probably a good idea. I also coated them with anti-seize before reinstalling them.

 

I agree with Dave that Toyota was trying to solve a problem in designing the new bed, I just think they rushed it into production without correcting a design flaw they clearly knew about (thus the massively oversized bolt hole to allow for relative motion between the bed and the frame). Considering the number of people who are experiencing this same excessive wear problem around this exact same bolt (only one of the six bolts in the bed), I'd say this is deserving of a voluntary recall or fix. If owners ignore the problem, the damage will accelerate as the bed wears & bounces more and more, and eventually severe and irredeemable bed damage could result.

Question for the group: has this been fixed in the 3rd Gen Tacomas?

I'm still not sure whether the wear is due to frame/bed flexure, or differential temperature expansion- if the former, it will predominantly affect those doing a lot of off-pavement driving; if the latter it will affect predominantly folks in southerly & hot regions. I'm in the "sour spot" on both counts, and the problem became obvious after 4yrs/24K miles.

The bulk of the abrasion is almost certainly between the bed and the frame, but there is also some wear under the bolt (you can see it in my photo). Since I already had more UHMW stuff than I needed, and since it was black, I elected to use it in both places, top & bottom. The UHMW is at least marginally compressible, so I'm hoping it will act as a filler, bumper, and sacrificial bearing surface.

Dave's also right that it would probably be wise to wire brush the bolt threads showing underneath the bed, before starting, to ease removal. In my case that was a dirty muddy job, but after spending a couple of hours getting the bolt out (with only liquid wrench as a helper), I will probably rethink this next time.

I did slather the threads with anti-seize before reinstalling, and I highly recommend doing that. Loc-Tite is *not* recommended, IMHO.