Tire and Weight Distribution Upgrades for Forest River Surveyor

Question

Question:

I have two queries I would welcome advice on. We have traveled some 4500 mls in our 2018 23ft 8in Forest River Surveyor MBLE travel trailer with a GVWR of 7480lb. Weve experienced tire problems, significant sway issues and what I call porpoising nose to tail dipping as occurs in the boating world. The T trailer is fitted with 4 Constancy 205/75 R14 tires with a load rating of 1760 lb. Allowing for the 10 of GVWR transfer to the tow vehicle via the hitch Im still concerned the tires are operating at close to their max limits. Within 77 lb in fact, if my calculations are correct. Were planning a major east coast to west coast and return trip this coming summer and Im keen to up grade both tires and suspension system to give greater reliabilty and safety margins. Additionally Im looking for a replacement sway control system. We currently have a dealer supplied and fitted Blue Ox sway pro BXW0550. It simply hasnt delivered as expected. Any suggestions you may have would be very much appreciated. Thanks and regards

asked by: Rob C

1

Helpful Expert Reply:

Since you are going across the country you are definitely doing the right thing in terms of trying to maximize your safety. The first thing to know is that your trailer tires should be rated to match or exceed your trailer's GVWR; your 205/75R14 tires, which are likely a load range C, do not have a high enough load rating for your 7,480 lb GVWR.

The first thing you should do is upgrade to the Kenda Karrier ST205/75R14 Radial Trailer Tire - Load Range D # AM10235. These have a maximum capacity of 2,200 lbs when inflated to 75 psi and a speed rating of 81 mph.

Next will be the upgrade to your weight distribution system and it does not surprise me that your current system is ineffective because the BXW0550 is rated for up to 550 lbs of total tongue weight, which you are almost certainly exceeding. I recommend the Equal-i-zer # EQ37120ET which is for TTW between 800 lbs and 1,200 lbs. Should your TTW be more in the 1,200 lb range I recommend going with the Equal-i-zer # EQ37140ET which is for TTW between 1,000 lbs and 1,400 lbs.

The Equal-i-zer is going to do a great job of controlling your sway; our customers who have used this system regard it very highly, with well over 400 reviews it has averaged nearly 5 out of 5 stars, as you can see on the product page. This system comes with everything you need for installation though it is recommended you use thin-walled socket # EQ70-00-4800 to help install the hitch ball.

In order to choose the best weight distribution system you will first need to know your total tongue weight (TTW), which is the tongue weight of your fully loaded and ready to go Forest River Surveyor plus the weight of any cargo behind the rear axle of your tow vehicle. The ideal system would be one in which your TTW would fall somewhere in the middle of the weight distribution system's tongue weight capacity.

Since tongue weight is roughly between 10 percent and 15 percent of your trailer's GVWR, even if you didn't have any cargo weight behind your rear axle the weight distribution system you were using would still not be rated high enough.

Based on your 7,480 lb GVWR and taking into account gear behind your rear axle a good estimate is that you have a TTW between 1,000 lbs and 1,200 lbs though it may be a bit higher.

I have added links to video reviews of the tires and Equal-i-zer for you to check out as well.