I bought my 2020 F250 6.7 diesel used so trying to get caught up on all the equipment available on this truck. I have been looking into the suspension on this truck because I tow a fifth wheel camper. I see on all the specs for rear leaf springs for the F250 as 4 leaf springs but i see no documentation on 3 leaf spring which my truck is equipped with. Can anyone tell me the specs for that setup and why this only has 3 and not 4? Also this truck has the STX trim package, I also see no documentation calling out STX how does this truck fit into the XL/XTL packages?

Has anyone upgraded there 2020 f250 to the high capacity tow package?
-Dana M275 axle
-5 leaf springs

Thanks for your help in advance.

 

What does your door jamb sticker say about the rear axle weight rating?

How big of a fiver are you towing and what is the pin weight?

 

3 leafs are the standard, base leaf pack under the 250. What is it that you are trying to learn about them? There may have been some who swapped to the 350 packs, but I have not seen where anyone did the rear axle swap too. Even with the HCTT pkg, Rear GAWR on sticker is the same as without. STX is an XL option pkg.

The base F-250, because of it's lower ratings, isn't the best choice for 5th wheel towing. Now if you are OK ignoring the ratings it will likely tow fine, but you might need some assistance from air bags in the rear to help mitigate sag.

 

Door jam sticker rear axle weight says, 6340 lbs. Fiver is 35'7", 13995 lbs GVWR & 2185 pin weight.

 

I'm trying to understand towing data vs what the truck is equip to tow. My thought was to at least change to the 350 rear spring pack. Changing out the axle will increase GAWR to around 7280. The Dana M275 axle is the same axle under the 2020 F350 SRW truck.

I'm trying to avoid buying another truck, making improvement to what I have is much more cheaper.

 

Your payload rating on your yellow sticker should be higher than that pin weight. Keep in mind that yellow sticker is meaningless.

Even if it's not, the "real" payload is based on the weakest link which is the rear tires, should have plenty of weight capacity there.

I would use Timbrens or airbags to reduce the sag, if it was my truck.

 

I think you are looking at about 2700 lbs pin wt.

take 20% of the trailer GVW. Ignore the salesperson and the advertisments. They usually go off of dry weight when it leaves the factory. It will never be that light again.

 

Swapping out the axle won't increase your GAWR per your sticker the 65 psi tire pressure and your springs will limit you to 6340, in the case of a m275 the 65 psi is giving you the 6340. The sterling 10.5 was the standard srw for both the 250s and 350s until 2017. IIRC it can handle 9000+ lbs. The ultimate gating factor in a SRW f350 is the OEM wheels at 3600 or a little over each.

I don't think swapping the axle would be worth it. The springs maybe, I have timbrens and a fifth wheel that I scaled at 2200 pounds of pin weight. Rides nice and level, handles very well with it and I am under my GAWR even at 6340.

 

I’m running the 275/70F18E tire load E rating, 3640 per tire, 7280 lbs. My pin hitch weight loaded will probably be around 2800. I’m thinking I will be fine with the Sterling axle on weight.

 

I would agree, the Sterling will be fine. When they used the Sterling under the pre-17 F-350, their rear GAWR was 7k. You might be a little under sprung in the rear, but you can find ways to help improve on that.

 

I agree the sterling is definitely up to the task. If it has the OEM 75w-85 fluid, probably not a horrible idea to step up to a 75w-140 but not a necessity. I put valvoline 75w140 in mine with a 08 aluminum diff cover, not required by any means but it is cheap and easy upgrade.



https://www.dormanproducts.com/p-28125-697-725.aspx

Here is what mine looks like with 2200 pounds on the pin, OEM springs with timbrens with a sterling 10.5 read end.

 

Looks good!!! What Reflection are you pulling, 337?

 

Thank you, it is a 324MBS. The living room and kitchen slides sit pretty much on the trailer axles and the bunk slide is just in front of it, no bed room slides so it is a little lighter on the pin than the 337 or the 311 despite being about the same size. I also put a goosebox on it, it is probably even with how much a slider would weigh but I don't need to find a home for 220-250 pounds worth of hitch, I toss the offset ball in my toolbox.