Question about increasing tow hitch capacity.

[draboo]

Our mh has a 4000 lb capacity hitch. The engine is a 275 hp Cummins with a 2000 MH transmission.

Can I safely install a 5000 lb hitch to tow 4500 lbs? Will this raise havoc with the transmission?

Thanks,eh?

Brad

[palehorse89]

Originally Posted by draboo

Our mh has a 4000 lb capacity hitch. The engine is a 275 hp Cummins with a 2000 MH transmission.

Can I safely install a 5000 lb hitch to tow 4500 lbs? Will this raise havoc with the transmission?

Thanks,eh?

Brad

Hi Brad, first is go over you Coach's weight numbers, GVWR & GCWR, and then get it weighed, loaded , ready to travel, do the math. Then you will call the Chassis manufacture and ask for their opinion and blessing on your wanted upgrade.
All's I could find is a Boucher from 03' http://media.rvusa.com/library/Holid...003neptune.pdf
Looks like there is a 24k GVWR and a 28k GCWR....... So if these numbers are correct for your Coach, get it weighed, it weighs in at lets say..., 22k.... then you can tow 6k.....if you can get the hitch upgrade approved!

[slowmachine]

I am working my way through the process of increasing the towing capability of my 2000 Holiday Rambler. I want to tow a 5,500-6,000 pound full-size pickup or SUV, but have a 5,000 pound hitch.

From conversations with manufacturers in the past week:

If you call Allison with you transmission model and serial number, they will tell you the maximum weight that the transmission is rated to handle. If you're operating in the upper end of that range, I would also ask what size cooler they recommend.

If you have a Freightliner chassis, they began installing hitches in 2002. From that point forward, they will tell you if your chassis can accommodate a heavier-duty hitch, with or without modifications. For earlier models, coach builders selected and installed the hitches, and Freightliner (and Holiday Rambler) will say nothing, avoiding liability for your modifications. Freightliner will also tell you the rated braking capacity of each axle, which may be important if the toad brake system fails.

Raw numbers don't tell the whole story, though. Increasing the towed load by a large amount, say from 5,000 to 15,000 pounds, will likely create handling problems that require suspension modifications to correct. As the ratio of coach weight to towed weight decreases. It becomes more difficult to stabilize the towed load.

[rodz]

Originally Posted by draboo

Our mh has a 4000 lb capacity hitch. The engine is a 275 hp Cummins with a 2000 MH transmission.

Can I safely install a 5000 lb hitch to tow 4500 lbs? Will this raise havoc with the transmission?

Thanks,eh?

Brad

Yes. With a tow bar you're adding no weight to the hitch. Even towing a 6,000 lb trailer is only a couple hundred lbs tongue weight. Other than on a steep hill you won't know it's behind you. Upgrade the hitch an go.

[palehorse89]

Originally Posted by rodz

Yes. With a tow bar you're adding no weight to the hitch. Even towing a 6,000 lb trailer is only a couple hundred lbs tongue weight. Other than on a steep hill you won't know it's behind you. Upgrade the hitch an go.

Sorry, I do not agree with this.......

Super BAD information! And when the OP 's transmission fail's , due to overload? or his Frame where the new, bigger hitch is mounted? Fail's......

Gross Combination Weight Rating (GCWR) Law & Legal Definition

Towing Terms and Definitions


GCWR - Gross combined vehicle weight rating (GCVWR)
Total combined weight of truck and trailer, including all passengers, fuel, fluids and cargo.

[Hooligan]

Originally Posted by rodz

Yes. With a tow bar you're adding no weight to the hitch. Even towing a 6,000 lb trailer is only a couple hundred lbs tongue weight. Other than on a steep hill you won't know it's behind you. Upgrade the hitch an go.

That would apply only to the GVWR, or weight added to the chassis. GCWR includes the combined weight of the towed vehicle and the chassis itself.. Both are determined by the weakest component in the drive train, suspension, brakes, and chassis construction as well as the hitch design.
Both limits in my motorhome are determined by the Allison transmission. The Allison 1000 is limited to 22,000# GVW even though the chassis is designed for 23K. The transmission limit for combined weight is 26,000. The placard reflects the lower transmission determined weights..
(Palehorse explained it better..)

[Moxy]

Originally Posted by Hooligan

That would apply only to the GVWR, or weight added to the chassis. GCWR includes the combined weight of the towed vehicle and the chassis itself.. Both are determined by the weakest component in the drive train, suspension, brakes, and chassis construction as well as the hitch design.
Both limits in my motorhome are determined by the Allison transmission. The Allison 1000 is limited to 22,000# GVW even though the chassis is designed for 23K. The transmission limit for combined weight is 26,000. The placard reflects the lower transmission determined weights..
(Palehorse explained it better..)

transmissions are rated on max torque, if the tranny is matched to the engine and motor is not upgraded there will be no problems, the tranny will not see anymore torque that what the engine can produce and as mentioned it will be matched to the engine, you will notice a performance difference up hills, you will need brakes in the towed vehicle with out question, as far as the frame, again depending on the builder the frames are used in several models with different ratings, I would not personally worry about 500lbs especially seeing you are not adding any huge amount of tongue weight.

Good Luck

Moxy

[jauguston]

If I were doing what the OP is considering one thing "I" would do is add a transmission temperature gauge with the sending unit installed at the fluid out to cooler location. That gauge will tell you how hot the transmission is being heated. Maximum fluid temperature limits are known and it is a good way to know how happy that transmission is. If the transmission has synthetic fluid the accepted safe maximum fluid temperature will be 300 degrees.

Jim

[slowmachine]

Originally Posted by jauguston

If I were doing what the OP is considering one thing "I" would do is add a transmission temperature gauge with the sending unit installed at the fluid out to cooler location. That gauge will tell you how hot the transmission is being heated. Maximum fluid temperature limits are known and it is a good way to know how happy that transmission is. If the transmission has synthetic fluid the accepted safe maximum fluid temperature will be 300 degrees.

Jim

Good point, and you may be able to access that data from the OBD-II port.

[Topflite51]

Is this one of the Roadmaster chassis' that had problems regarding the trailing arms issue? I would call Source Engineering and get their opinion regarding beefing up chassis for towing more than designed.

[jauguston]

If the transmission fluid temperature data is available from the OBD port it is still important to find the location of the sending unit. It may very well not be in the right place. The correct location is at where the fluid comes out of the transmission and goes to the cooler. I have hears of some sensors being stuck in the test port that is a dead end passage with no fluid flow past it. My coach has a factory installed gauge and the sensor is in the right place.

Jim

[draboo]

thanks for the replies. We were looking into flat towing a Jeep Cherokee Sport, which weighs in at about 3200 lbs. Maybe I don't need to upgrade the hitch. I was thinking we may use the Jeep for storage, but 800 lbs is quite a bit of extra stuff to haul.

I will be using a smart phone to monitor engine health.

Side note: finding a Cherokee in nice condition (pre 2001) is proving to be a challenge in the PNW.

Oh, and GO SEAHAWKS!!

[rodz]

Originally Posted by draboo

thanks for the replies. We were looking into flat towing a Jeep Cherokee Sport, which weighs in at about 3200 lbs. Maybe I don't need to upgrade the hitch. I was thinking we may use the Jeep for storage, but 800 lbs is quite a bit of extra stuff to haul.

I will be using a smart phone to monitor engine health.

Side note: finding a Cherokee in nice condition (pre 2001) is proving to be a challenge in the PNW.

Oh, and GO SEAHAWKS!!

if that's all you're towing I wouldn't change anything. Hook it up and go.

[jauguston]

I would agree.

Jim