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Old 08-13-2012, 09:04 PM   #15
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I a not an expert on this but I will give some of my thoughts, based on my experience weighing mine.

It looks like your trailer is adding about 800# to the truck which would seem to be the tongue weight. When I weighed mine, my numbers looked like I had a tongue weight of 400# with a trailer weight of 5040# loaded. That was far less than the 10% to 15% recomended. I bought a Sherline scale and weighed my tongue at about 625#, ... much better. It gets complicated because the WD hitch puts some truck weight on the trailer and some trailer weight on the truck.

Based on that I would guess your real tongue weight is over 800#. Based on 5200# trailer weight, 15% would be 780#, 12% would be 624#. Maybe lightning the tongue a little would bring the total load on the truck down under the 7150# rating on the truck but it doesn't look, to me, as if you are overloaded.

Hopefully someone with more experience will give you better info.
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Old 08-13-2012, 09:28 PM   #16
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Quote:
Originally Posted by markbrit View Post

except I only got 2 weighs in not the 3rd one without weight distributing disabled. Ugh... I forgot! Oh well I plan to return when I have truck/camper fully packed.
That one missing weight is going to hurt a little. Not a bunch but there are some things you will not know.

Quote:
Originally Posted by markbrit View Post

This is included on both weights:
500 lbs of passengers included
50 lbs of tools in bed of truck, otherwise empty.
14 gallons of gas in a 26 gallon tank (84 lbs)

Ticket #1 - truck & trailer with WD hitch hooked up:
Steer Axle - 3,600 lbs
Drive Axle - 3,580 lbs
Trailer Axle - 4,400 lbs
Gross Weight - 11,620 lbs

Ticket #2 - truck with no trailer:
Steer Axle - 3,700 lbs
Drive Axle - 2,720 lbs
Trailer Axle - 0 lbs
Gross Weight - 6,420 lbs

Initial thoughts:
Was surprised my front end lightened up with WD connected. I think I feel OK with it though as drive was smooth and comfortable. No floating.

Both axles are below max range.
Good for you!!! You done good except that on missed weight. The first time weighing can be a bit nerving. And yes your front end is a little light. Getting 50# or so closer may show some handling better. Just do not go over unhitched weight. If you where not fully loaded this will all change and you need to tweak the WD hitch to get some more weight up front.

Quote:
Originally Posted by markbrit View Post

If I did my math right I see trailer weigh in at 5,200 lbs. GVWR is 7,000 lbs.
Yes, by default if the truck is 6,420# and the GCW is 11,620# then what is left is the TT GVW at 5,200#.

Quote:
Originally Posted by markbrit View Post
Tires are OK. They are below weight spec of 4,700 lbs and at 55-60 mph they felt good at 44 psi for a 50 mile test drive. So plan to test them on a few upcoming trips.

GCWR from Toyota is 16k, so feel good.
Boy they sure uped the pull ratings on these tons. 16K GCWR on a ton truck. My 2003 K2500 Suburban was rated at 16K GCWR and so were the 2500 HDs of that time frame. Pulling you should be good and have reserve towing capacity

Quote:
Originally Posted by markbrit View Post
OK my two questions:

GVWR of truck is 7,150 lb by looking at sticker in door jam. GWVR of truck from slip #2 is 6,420 lbs. Combined weight of both axles with trailer connected (slip #1) is 7,180 lbs. Should I be concerned?

Can I figure Tongue weight?

Looking forward to your feedback and thanks for reading my short story!

thanks - Mark
Your 1st question on GVWR. Your right in your thinking. The GVWR of the truck is 7,150# and the GVW when the TT is hitched is 7,180# or by the weight tickets 30# too heavy. There can be 50# of scale error so if you weigh again you might be just under. End result, you are sitting on top of the GVWR of the truck.

This is the Achilles heal of a ton truck. In your case you have a lot of pulling power, just you are shy on payload. If you are pulling a boat, not so much and issue. A TT , a different story. Putting 150# of firewood, (not really much) and a bunch of other camping gear in the truck bed and you will be well over the GVWR. That rating is a real number as declared by the manufacture. It is a limit. While your axle weights are not into issues, going way over the GVWR is a condition that is not in accordance with the manufactures rating. Only Toyota engineering will know exactly where the weak spot is and why they put that rating there. Is it because the truck brakes are only rated to stop that amount of weight with safety factor? Is it a vehicle stability rating? This question has been beat to death in many camping forums. My friendly advice is to respect it and now that you know it, try and stay at or below it.

See this post and after reading you decide. If needed I can find others too. http://www.sunlineclub.com/forums/f72/towing-article-on-ratings-13179.html

The tongue weight, this is where that missing 3rd weight is going to hurt. All you know is:

The TT GVW is 5,200#.

The TT axle weight with WD engaged is 4,400#

The missing part is, how many pounds did WD shift from the rear axle of the truck to the TT axles? That 3rd weight shows this and allows you to subtract the truck alone GVW from the truck TT and TV hitched weight but without the WD engaged number to get an actual tongue weight. You might have shifted 100 to 150# to the TT axles and this is included in the 4,400# number. There is a mathematical way to back into this, but after a long page of calculations after you give me all the axle distances, it is still only an estimate.

Here is a WAG 5,200# - 4,400# with WD = 800# minus a WAG of weight shifted of 100 to 150# to the TT axles = 700 to 650# tongue weight. 700# is 13.5% TW and 650# is 12.5%.

Good for you for doing this. Now you are learning and helping a lot of other folks help sort out their rigs from your good work.

Hope this helps

John
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Old 08-14-2012, 07:40 AM   #17
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Good feedback fellas, thanks. Ahh the curse of compromise of less truck for better gas mileage and comfort of ride. I do miss the old days of a 3/4 ton truck and just stuffing it full of stuff

Agreed at upper threshold of GVWR. I do not tow with water tanks full so will need to tweak/adjust onboard items a bit and perhaps pack the trailer rear more to spread load.

I am going to revisit the hitch setup and see if I am pushing a bit too much of the trailer weight onto the truck.

Also want to be sure I do not lighten the tongue weight too much and get the backend of trailer swaying.

Sounds like another Saturday at the truck scale!
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Old 08-14-2012, 10:11 AM   #18
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I haven't made it to the CAT scales, myself, but I did weigh the 2653 at a metal recycle place and it weighed 6200 lbs. (2 batteries, two 30 propane tanks, half tank of water, pots&pans, etc.). I towed it with a 1st generation '05 Tundra, but was really pushing it.
My experience towing with the '10 Tundra just as it came from the dealer has been successful under a variety of conditions. To wit: 1) Idiot u-turns in front of me at 55 mph. Two successive, abrupt lane changes made with no loss of control or sway.
2) Passing oncoming log truck at bottom of a hill on a two-lane country road at combo speeds of at least 100 mph, no sway, no maneuvers needed.
3) Several trips through the mountains of Va. and W.Va., up and down steep grades and winding roads. Not a problem.
Towing, I keep the tach under 2500 rpm to help with fuel mileage. If this means going up a steep grade at 30 - 40mph, so be it. Descents are always more tricky (never see a runaway truck ramp on the uphill side, do we?) so I go slower yet, descending at 25 mph on a 13% grade. I noticed brake dust on my rear wheels after that trip (4-wheel disc brakes).
I think Mark is good-to-go as is, personally.

Anecdotally yours,
Teach
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Old 08-14-2012, 10:24 AM   #19
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Thanks Teach! I feel OK with towing with factory tires and overall the Tundra felt great pulling last weekend.

I would like to get the GVWR of the truck down when loaded to tow. Just for the option of adding another passenger or a bit of stuff in my truck bed for future trips.

I called equalizer hitch and we discussed some options to lighten the load. I will make adjustments and head back to CAT scale next Saturday.

I think I am in a good place but now the numbers/stats are obsessing me and I want to be dialed in for max efficiency.

Stay tuned...thanks.
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Old 08-21-2012, 08:23 PM   #20
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Back again and made the trip to the CAT scale. I spent 3 hours tweaking adjusting ,etc.
So here is what I am going with.

Ticket #1 - truck with no trailer: (truck had full tank of gas, 400 lbs of passengers and 75 lbs of tools/spare tire.)
Steer Axle - 3,580 lbs
Drive Axle - 2,700 lbs
Trailer Axle - 0 lbs
Gross Weight - 6,280 lbs


Ticket #2 - truck & trailer with NO WD hitch hooked up:
Steer Axle - 3,240 lbs
Drive Axle - 4,000 lbs
Trailer Axle - 4,320 lbs
Gross Weight - 11,560 lbs


Ticket #3 - truck & trailer with WD hitch hooked up:
Steer Axle - 3,700 lbs
Drive Axle - 3,280 lbs
Trailer Axle - 4,580 lbs
Gross Weight - 11,560 lbs


I talked with equalizer and they felt OK with my setup. The added 120 lbs on the front axle was within their range and since the axle is rated for 4k I think we are good.
Not much room to pack stuff but that is OK as most stuff goes in the camper except for the kids bike. Way I see it I have another 170 lbs to go before I hit the trucks gvwr.
Overall happy with the compromise. any thoughts?
John I think my tongue weight is 700 lbs?
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Old 08-22-2012, 10:22 PM   #21
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Mark,

Your tongue weight is:

TV GVW hitched with no WD TV alone GVW = tongue weight

Filling in the numbers:
From Weight 2: (3,240 + 4,000) - From Weight 1: (3,580 + 2,700) = 960# tongue weight

How did you arrive at 700? I rechecked my math 3 times and still come up 960# Just checking I did not mix it up.

Your camper GVW is: GCW with no WD TV only = TT GVW.
Filling in the numbers:
From Weight 2: 11,560 From Weight 1: 6,280# = 5,280# GW of TT

960/5280 * 100 = 18.2% loaded tongue weight. It should tow stably.

Now to your WD adjustments. I need to type some more on this and Im out of time tonight. Im not a fan over overdriving the front end down 120# and I want to explain why but Im out of time.

If you called Equal-I-zer and they told you it was OK to over drive the front end of the TV by 120#, well they changed their tune again.ERRRR. That is their old thinking from years ago of equal drop front and rear and not what they preach today following the new SAE towing guidelines. Or what many new truck manufactures recommend. I wanted to explain this so folks following along can see where Im coming from and why, jsut need a little more time.

Do this for me, look up in your Toyota manual for towing with a WD hitch and see what they say about the front end. Toyota pulled their manuals from the open web unless you have a VIN so I cannot look it up for you.


Tell me what they recommend on the adjustment. It should be in the towing section. Copy the exact words they state, if they state anything. Not all brands actually tell you how to adjust the WD. Ford, GM and Dodge do now a days. They did not allows though.

Here see the top of page 18 of a new Equal-I-zer hitch. http://www.equalizerhitch.com/pdf/eq...anual_0111.pdf

They talk about being above unhitched height, not below it. They use to preach adjusting below unhitched height and that created havoc with some truck front ends, some truck receivers and oversteer. Understeer and oversteer - Wikipedia, the free encyclopedia

Be back on Thursday.

Thanks

John
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Old 08-23-2012, 05:18 AM   #22
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Hi John,

I had a weird calculation on tongue weight, it was a guess by deducting trailer weight from WD and non WD slips. Was not sure how to calculate.

Wow 960 seems a bit heavy but it does tow nice. I guess trailers with kitchen in the front just weigh more in the front?

Both equalizer manual and Toyota manual suggest matching the unhitched weight on front axle. I too was concerned when crunching the numbers and that is why I called them. But 120 lbs is only about 3.5% of additional weight and axle is rated for 4k lbs. They felt it was within the tolerance.

When driving, truck does feel a bit more grippy to the ground but not feel pressed down into the road. I have a short road trip with the camper on Saturday and will test again.

I do have another weight slip and with less tension on spring arms get the following reading. So if needed I will adjust.

Ticket #4 - revised setup truck & trailer with WD hitch hooked up:
Steer Axle - 3,560 lbs
Drive Axle - 3,480 lbs
Trailer Axle - 4,500 lbs
Gross Weight - 11,540 lbs


Thanks for caring!
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Old 08-23-2012, 10:06 PM   #23
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Hi Mark,

Years ago it was thought that “equal squat” on the front and rear of the TV was the correct way to adjust WD. This concept on purpose drove the front end down below unhitched height and weight.

Tests by RVIA and SAE have since shown this is not a good thing to do any more. Actually back in the 70’s the NHTSA hads a towing study done pulling TT’s by TV’s of the time. The firm who did the study for NHSTA reported the same thing now that SAE has concluded. If you want, I can find that NHTSA study on line and link it here. I printed it off a few years ago and I still have the 1” thick report down in the basement.

To summarize this, the concerns are oversteer in the TV. Understeer and oversteer - Wikipedia, the free encyclopedia

When the front end of the truck is heavier then unhitched it creates more grip to the road. While this may sound like a good thing, it can be a really bad thing when towing a TT. The concern is the front end will “bite in” so to speak in a sharp turn and rather then sliding some like normal, it does not and sends the truck into jack knife. While this was known in the early 70’s by that NHTSA report, it never made it to a formal recommendation until a few years ago. This directly conflicted with the equal squat theory.

Equal-I-zer is now on board with “not” overdriving the front end below unhitched. In fact the actual directions state the front end should be above unhitched. On page 17 and 18 http://www.equalizerhitch.com/pdf/eq...anual_0111.pdf Equal-I-zer states the front end to be higher than unhitched.

Here is a link to what an RV member has claimed Equal-I-zer wrote him. The verbiage used and technical nature of the content suggests it is factual. It also matches page 17 and 18 of the Equal_I-zer manual.
RV.Net Open Roads Forum: Towing: Advice on setting up Equalizer Hithch...

Ford has also got on board with this same type of recommendation for WD adjustments. Here is right out of a 2012 F150. See page 276 under weight distribution hitches
http://www.motorcraftservice.com/pubs/content/~WOCF12/~MUS~LEN/36/12f12og3e.pdf

GM, is still stating to return the front end to unhitched height as this time.

The days of overdriving the front end are gone or going quickly.

There is also steering geometry involved. If you adjust the WD hitch to return to unhitched height or weight to slightly above, the steering geometry and tire wear is normal as your truck is riding around unhitched. Now there is another realization about a WD hitch. The WD on the front of the truck is changing as you tow. If you always towed on perfectly flat land then the WD would stay the same. The reality is, we go up RR track crossings, down steep hills, up over bumps, hard banked turns, any type of turn where the TT is on a different level of ground then the TV in a turn etc. When the truck and TT are at and angle to each other WD changes. The front end gets driven down or up pending which way the angle was between the TV and TT.

So if you are 120# heavy on purpose now, when you go up a quick hill like some RR track crossings, the WD bar loads up more and that 120# over drive can turn into 240# or higher over drive. Now you are really biting in if this is a turn as well. We cannot stop this shifting of WD, it just happens however we can control to not make it worse than it already is by not overdriving the front end.

Then there is the rear of the truck breaking free of traction in wet and or slippery conditions when the camper is pushing the truck. When this conditions happens, that extra weights on the rear axle helps more prevent a lose of traction then having extra weight on the front axle.

The truck receiver is in the middle of this too. If Toyota declares the front end to be returned to unhitch height and you have an OEM receiver, they may have designed that receiver to match up with the WD recommendation in the owner’s manual. They know a WD hitch takes a lot of ups and downs and make it heavy enough to take that. However they may not make to extra heavy to over drive the front end plus the normal towing dips and hills.

Toyota on the older Tacoma’s had a 750# rated WD receiver. I helped a few RV’ers with that truck after they bent their receiver up in the air. In this case one of them was using 1,000# WD bars on a 750# receiver. When these back flexes happen the receiver has to take it or permanently bend and his did. The other buddy had a Reese round bar head and a DC. He had a double whammy. The Reese round bar head has very little rear tilt. And his older Taco receiver really flexed. Basically with 750# WD bars he could not get his front end anywhere close to unhitched height on a 700# tongue weight. He was way high. He bought an aftermarket receiver and now all is OK.

I’m not saying your new receiver has the issues of the older ones, just don’t on purpose overdrive the front end for the reasons listed above.

Your spare weight set # 4 is a lot better. Basically with are back to unhitched weight on the front end. I would go with that setup.

Ticket #1 - truck with no trailer: (truck had full tank of gas, 400 lbs of passengers and 75 lbs of tools/spare tire.)
Steer Axle - 3,580 lbs
Drive Axle - 2,700 lbs


Front 120# heavy
Ticket #3 - truck & trailer with WD hitch hooked up:
Steer Axle - 3,700 lbs
Drive Axle - 3,280 lbs


Front 20# heavy
Ticket #4 - revised setup truck & trailer with WD hitch hooked up:
Steer Axle - 3,560 lbs
Drive Axle - 3,480 lbs


Hope this helps

John
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Old 08-24-2012, 09:39 PM   #24
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OK John will switch it up to #4 and go 20 lbs lighter in the front end. Good info, thanks.
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