CAT Scales and weight distribution

[Ponyfvr]

I have a 2015 Toyota Tundra with a Crewmax cab, TRD 4x4 package, LTD package and a 5.7 L V-8. I also have a 2015 25' AS International.

I weighted the truck and trailer this morning at a CAT scale, the trailer tanks were pretty empty and the trailer had clothes food etc. The truck had a full tank of gas and a YETI cooler and some gear in the truck bed. I have a Husky Centerline Hitch.

Here are the weights:

Steer Axle 3100 lb
Drive Axle 4300 lb
Trailer Weight 5580 Lb
Gross Weight 13,000 Lb

Not sure what all this means???????? Am I OK?

[HowieE]

Not sure what your question is but to be effect from an analysis stand point we need the truck axle weights without the trailer.

Are you using a WD hitch?

From a towing standpoint it would be nice to know what the rear axle ration is.

[Ponyfvr]

Originally Posted by HowieE

Not sure what your question is but to be effect from an analysis stand point we need the truck axle weights without the trailer.

Are you using a WD hitch?

From a towing standpoint it would be nice to know what the rear axle ration is.

Thanks I don't know the axle weights, I will weigh the truck without the trailer. I am using a Husky Centerline WD hitch. I will check on the axle ratio.

Thanks

[MacPDX]

Look at the sticker on the driver's door frame that contains max ratings for each axle and GVWR. I have a 2014 DC TRD and my max ratings are:

Front: 4000
Rear: 4150
GVWR: 7100

So, based on these numbers, you are heavy by 150 lbs on the rear axle and 300 lbs overall. Based on my numbers, your front axle looks light; mine is around 3400 lbs unloaded and with WD applied when hooked to the trailer.

Check your WD setup to insure you are returning the front axle back to its original weight. Once you do this, you will probably be fine. If you have more to add to the truck, like people, pets, etc, you will need to reload your trailer, moving some weight behind the axles.

[MacPDX]

All Tundras with the 5.7 have a 4.3 rear differential ratio.

[ghaynes755]

Bob I'm attaching a spreadsheet that I built. See this post on how to get do the weighing. http://www.airforums.com/forums/f464...ml#post1111379

Basically you will have a minimum of 3 times over the scales. Once with TV/TT hooked up and WD turned on, once with TV/TT hooked up but WD function turned off/disconnected and once with just the truck. And you will have the front TV wheels on the front scale, rear axle on the middle scale and the trailer axle on the third scale.

Typically CAT will charge $10 for the first one and $2 for any additional at the same scale location and within 24 hours. When my local CAT scale isn't busy I can drive on, do the first weigh. Then go pay for that one. Tell them I am going to do a couple of more without leaving the scales. Pull back on, take some tension off of the jacks on the ProPride, weigh, repeat until I have the jacks at the bottom where everything is loose.

Drive off, drop the TT and weigh the truck.

Fill in the proper fields in the spreadsheet and you can compare the results based on your various adjustments. Your owner's manual should also give an indication on what they consider a good towing setup. GMC says measure to the top of the front wheel well without the trailer then add back in 1/2 of the distance when you hook up (front end rises without WD). That works pretty well.

Good luck.

CAT Calc Sierra 2500 Classic 5-2-15.xlsx

[Ponyfvr]

Originally Posted by ghaynes755

Bob I'm attaching a spreadsheet that I built. See this post on how to get do the weighing. http://www.airforums.com/forums/f464...ml#post1111379

Basically you will have a minimum of 3 times over the scales. Once with TV/TT hooked up and WD turned on, once with TV/TT hooked up but WD function turned off/disconnected and once with just the truck. And you will have the front TV wheels on the front scale, rear axle on the middle scale and the trailer axle on the third scale.

Typically CAT will charge $10 for the first one and $2 for any additional at the same scale location and within 24 hours. When my local CAT scale isn't busy I can drive on, do the first weigh. Then go pay for that one. Tell them I am going to do a couple of more without leaving the scales. Pull back on, take some tension off of the jacks on the ProPride, weigh, repeat until I have the jacks at the bottom where everything is loose.

Drive off, drop the TT and weigh the truck.

Fill in the proper fields in the spreadsheet and you can compare the results based on your various adjustments. Your owner's manual should also give an indication on what they consider a good towing setup. GMC says measure to the top of the front wheel well without the trailer then add back in 1/2 of the distance when you hook up (front end rises without WD). That works pretty well.

Good luck.

Attachment 239481

Wow this is great thank you very much. I will go back to the scales

Thanks again

[Ponyfvr]

Originally Posted by MacPDX

Look at the sticker on the driver's door frame that contains max ratings for each axle and GVWR. I have a 2014 DC TRD and my max ratings are:

Front: 4000
Rear: 4150
GVWR: 7100

So, based on these numbers, you are heavy by 150 lbs on the rear axle and 300 lbs overall. Based on my numbers, your front axle looks light; mine is around 3400 lbs unloaded and with WD applied when hooked to the trailer.

Check your WD setup to insure you are returning the front axle back to its original weight. Once you do this, you will probably be fine. If you have more to add to the truck, like people, pets, etc, you will need to reload your trailer, moving some weight behind the axles.

I checked the sticker and my GAWR is the same Front 4000 and rear 4150 my GVWR is 7200. WE are on the road so I will try and find a scale and unhook the trailer and get a weight for the truck only.

Thanks for your help

[HowieE]

The column numbers are MAX. load by manufactures design. Not to be used in this case. You will need actual empty scale axle weights.

Another important consideration when setting up is the fact that an Airstream MUST ride parallel to the ground. This means the ground to frame measurement has to be as close as possible front and rear of the trailer. Riding tongue high will result in additional tongue weight from the trailer. Riding tongue low will result in less tongue weight from the trailer.

[slowmover]

Do all three weights at the same time. Full fresh water, propane and truck fuel. Cross the scale with WD tensioned, second pass untensioned, and then drop trailer and do truck solo for third pass. No changes with passengers etc. Be in the truck when weight taken.

The numbers from those three are the basis for any changes.

[m.hony]

Your numbers mean to me that your rig is 1,400# lighter than my rig. I guess 5' more of trailer weighs about 1,400#. My Tundra CrewMax and 30' Classic are 14,400# combined. Full tank of gas, me, my wife, and cat on board, firewood and bicycles in the truck bed, groceries and clothes for 10 days camping.

[Ponyfvr]

I adjusted the WD and it added 80# to the steer axle (3100 to 3180) and took 100 # from the rear axle (4320 to 4220) the trailer axle went from 5660 to 5580 and the total gross weight went from 13000 to 13060, we have some water in the tanks that might explain the extra weight. After the WD adjustment the truck seemed to be more level and it also handled better. I will check the level of the AS when we get back home.

Thank you everyone for your suggestions they were very helpful.

[GammaDog]

I have almost the same rig... 2014 tundra crewmax, 5.7, limited 4x4 (but not TRD), 25' 2014 Eddie Bauer. I recently did all three passes as described above at a CAT scale. Without looking up the particulars on your truck and trailer it looks to me like you might want more WD dialed in.

I had full fuel, full fresh, a passenger, generators and bikes, etc. I was as close to ready for a long trip as I could simulate short of loading the fridge with food. Here are my weights:

With WD bars on:
Truck front axle: 3560
Truck rear axle: 3800
Trailer: 6020

With weight bars in the truck bed:
Truck front axle: 3200
Truck rear axle: 4340
Trailer: 5840

Truck alone (with hitch removed also)
Truck front axle: 3580
Truck rear axle: 3040

My year and config has a GCWR (total of truck and trailer) of 14,800. Yours should be similar if not identical. Your 13,000 or my 13,380 are both well under that.

My GVWR (weight on the trucks front and rear axles added together) is 7200. I'm 160 lbs over that. You may be 200 over. Frankly, I'm not too worried about that. I will lighten cargo, take a half tank of fresh water or leave a kid behind and be fine.

My front axle is rated to 4000 and rear at 4150. I'm fine with the WD bars on since I'm moving weight to the front of truck and to the trailer's axles but you can see I overload the rear axle without the WD bars in place. If your truck has the same ratings, you are over on the rear, too. I'm thinking your front is lighter with the trailer on than without. Toyota (at least for the 2014 model year) recommends compensating the tundra with sufficient WD support to bring the front wheel well back to the same height with the trailer as it was without. You can measure that without going back to the scales to see if you are close.

My trailer is fine either way. You can see that my equalizer hitch as set up pushes 180 lbs of trailer weight back to the trailer rather than the truck. It also moves 360 lbs from the truck's rear axle to the front.

The tongue weight is also good with the hitch on. It's 740 lbs. However, at this much WD dialed in, I've put the tongue weigh at 10.9% of the trailer weight. I'm not included to go lower (more WD) since I don't want to go under 10% for trailer handling reasons.

Not sure if any of that helps, but it's a recent set of tests on a very similar rig to yours.

I'm open to feedback from the real experts since I'm still a nube and this was my first set of measurements of my tuck and trailer.

[HowieE]

Originally Posted by Ponyfvr

I adjusted the WD and it added 80# to the steer axle (3100 to 3180) and took 100 # from the rear axle (4320 to 4220) the trailer axle went from 5660 to 5580 and the total gross weight went from 13000 to 13060, we have some water in the tanks that might explain the extra weight. After the WD adjustment the truck seemed to be more level and it also handled better. I will check the level of the AS when we get back home.

Thank you everyone for your suggestions they were very helpful.

You can not adjust the WD hitch without adjusting the trailer level at the same time. They are interactive. The truck level is not a goal to work towards. The truck orientation is a function of the more important WD hitch and trailer adjustments.

Your numbers are in the right direction. You might consider this trick. Place a piece of painters tape on the front fender of the TV. Measure and mark a height on the tape. After all adjustments remeasure and mark. The second measurement wants to be at or slightly above to the original mark. It does not want to be below the original mark. What this is doing is getting the front axle geometry back to original. Large difference in this will cause por steering control.

[Ron Gratz]

Originally Posted by GammaDog

The tongue weight is also good with the hitch on. It's 740 lbs. However, at this much WD dialed in, I've put the tongue weigh at 10.9% of the trailer weight. I'm not included to go lower (more WD) since I don't want to go under 10% for trailer handling reasons.

The indicated tongue weight is (3200+4340) - (3580+3040) = 920#.

With WD applied, the net load added to the TV's axles was 740#, and the load added to the TT's axles was 180# -- also giving an indicated tongue weight of 920#.

The indicated tongue weight percentage was 920/6769 = 13.6%.

However, the WDH should have been in the receiver when the "Truck alone" weights were obtained.
Assuming the WDH weighs 80#, it would have caused about 40# to be removed from the front axle and about 120# to be added to the rear.
This would have changed the front axle weight to 3540# and the rear to 3160#.

With the WDH in the receiver for the "Truck alone", the indicated tongue weight would have been about 840#, and the TW% would have been about 840/6680 = 12.6%.
The front axle load when hitched with WD applied would have been 3560 versus an adjusted "Truck alone" weight of 3540#.

I would not try to achieve more WD.

Ron

[GammaDog]

Thanks for the feedback, Ron.

As I read your comment it appears that the proper way to measure tongue weight is without the WD bars in their functional position? The weights you chose for the truck with trailer were that pass (3200 + 4340) as opposed to the pass I chose which has the weight bars tensioned and produced (3560 + 3800). That choice produces the 740 versus 920 tongue weight.

I believed the measurements and calcs should compare the truck without trailer or hitch gear versus the truck and trailer set up for travel. Did I get that wrong?

[Ponyfvr]

Originally Posted by Ron Gratz

The indicated tongue weight is (3200+4340) - (3580+3040) = 920#.

With WD applied, the net load added to the TV's axles was 740#, and the load added to the TT's axles was 180# -- also giving an indicated tongue weight of 920#.

The indicated tongue weight percentage was 920/6769 = 13.6%.

However, the WDH should have been in the receiver when the "Truck alone" weights were obtained.
Assuming the WDH weighs 80#, it would have caused about 40# to be removed from the front axle and about 120# to be added to the rear.
This would have changed the front axle weight to 3540# and the rear to 3160#.

With the WDH in the receiver for the "Truck alone", the indicated tongue weight would have been about 840#, and the TW% would have been about 840/6680 = 12.6%.
The front axle load when hitched with WD applied would have been 3560 versus an adjusted "Truck alone" weight of 3540#.

I would not try to achieve more WD.

Ron

Ron the truck only weight was with the Husky hitch installed in the receiver hitch but not the parts that attach to the trailer or the WD bars. The hitch weighs 80# (I weighed it last week at home using a bathroom scale)

Thanks for your help.

[The Ice Man]

All good advice here. Two other things you can do. Cross the scale with one side of the wheels on the apron and the opposite side on the scale. That way you can determine individual wheel weights except the trailer tire weights will be combined. OR - Go to an Escapees SmartWeight site or Rally.

Can't say enough good things about their program and Mark Nemeth who runs it. With SmartWeight you get actual individual tire weights. I'm on the road and the weight sheet is at home, but as I recall the first time my front 27FB axle weights were in the neighborhood 1700#s +/- each tire and the rear were 1200 or 1300#s +/- each. The floor was close to dead level using a carpenter's level. Mark suggested I raise the hitch ball upward one inch. The floor still measured close to dead level, but the trailer tire weights shifted to 1500#s +/- each tire. I measured with 5 gals in each waste tank and 30 gals. fresh water, full propane, full provisions for hitting the road.

BTW the tongue weight was 990#s.

I can't tell a lot of difference in the tow feel, but I feel more comfortable that each tire is carrying it's own load.

[Ron Gratz]

Originally Posted by GammaDog

As I read your comment it appears that the proper way to measure tongue weight is without the WD bars in their functional position? The weights you chose for the truck with trailer were that pass (3200 + 4340) as opposed to the pass I chose which has the weight bars tensioned and produced (3560 + 3800). That choice produces the 740 versus 920 tongue weight.

Tongue weight is the vertical load which is imposed by the coupler against the ball when WD is not activated.
If you use the load on the TV axles obtained with "the weight bars tensioned", you will not be calculating the correct tongue weight.
Your calculated tongue weight will be too low by the amount of load transferred to the TT's axles

I believed the measurements and calcs should compare the truck without trailer or hitch gear versus the truck and trailer set up for travel. Did I get that wrong?

The weight of the WDH is not included in the "tongue weight".
Since the load on the TV, with TT attached, does include the weight of the WDH, the "Truck only" weight also must include the weight of the WDH.

If you make the "Truck only" weighing without having the WDH in the receiver, your calculation of tongue weight will be too large by an amount equal to the weight of the WDH.

Ron

[ghaynes755]

Adding to Ron's comments for those that have ProPrides. When I got my last setup from Sean the weight of just the head was about 80#. Since that isn't going to come off the trailer on a CAT scale you could adjust the tongue weight by subtracting the 80#. Ron, have I got that right? Would you also delete the weight of the bars since they are attached to the head?