F350 vs F250 rear springs

[Hans_ky]

When I was researching my truck to order I found a bit of uncertainty regarding the rear spring packs. If it’s of any value to those still contemplating I’m attaching a shot of what I believe is my spring pack part number. This is from an F350 KR Tremor 7.3l with 10k GVWR (derated). Maybe someone with an F250 could post their part number and we could put this to rest?
PN LC3C-54975-NA

 

[thevol]

When I was researching my truck to order I found a bit of uncertainty regarding the rear spring packs. If it’s of any value to those still contemplating I’m attaching a shot of what I believe is my spring pack part number. This is from an F350 Tremor. Maybe someone with an F250 could post their part number and we could put this to rest?
PN LC3C-54975-NA

This is off my F250 with 7.3L, 4.30 gears, and 10k GVWR.

 

[Bruno]

This is the passenger side spring on my 250 XLT 6.7

 

[Mike Alcocer]

With the difference between the 6.7 and 7.3 being that the 6.7 has an overload spring pack above the main? 6.7 gcvw are both the same for 250&350

 

[Hans_ky]

With the difference between the 6.7 and 7.3 being that the 6.7 has an overload spring pack above the main? 6.7 gcvw are both the same for 250&350

I guess all the 350s have the overload springs, then? My 350 is 7.3 with 10k GVWR.

 

[Mike Alcocer]

Interesting. Seem to be the same between them. Be curious to confirm this with a 6.7 350. The 6.7 allows for a trailer tow package that ups the weight to the 30k. Wonder if that's all drive train. I do think they have different rear axles between gas and diesel

 

[Hans_ky]

Interesting. Seem to be the same between them. Be curious to confirm this with a 6.7 350. The 6.7 allows for a trailer tow package that ups the weight to the 30k. Wonder if that's all drive train. I do think they have different rear axles between gas and diesel

I have read the transmissions are definitely different between the diesel and gas trucks, too. My truck has the Dana M275 rear axle, which I think is the same as the diesel.
Thanks for everyone helping figure this out!

 

[cadcam1]

I have read the transmissions are definitely different between the diesel and gas trucks, too. My truck has the Dana M275 rear axle, which I think is the same as the diesel.
Thanks for everyone helping figure this out!

I

 

[cadcam1]

Ford 10R140 TorqShift 10 Speed Automatic Transmission Specs & Ratios

Ford 10R140 TorqShift transmission specifications, gear ratios, and operational features. The 10R140 TorqShift is a 10 speed automatic transmission developed for and introduced to the Ford Super Duty platform (F-250, F-350, F-450, F-550, F-600) for the 2020 model year. The 10R140 10 speed...

www.dieselhub.com

 

[thevol]

I guess all the 350s have the overload springs, then? My 350 is 7.3 with 10k GVWR.

My F250 7.3 looks identical to that with overload springs. Doesnt seem like there is any physical difference between them, strange.

 

[Hans_ky]

My F250 7.3 looks identical to that with overload springs. Doesnt seem like there is any physical difference between them, strange.

Do you have the Dana rear axle too?

 

[thevol]

Do you have the Dana rear axle too?

Yes

 

[Chris21667]

Yes

What Dana is it a 60 or 70?

 

[thevol]

What Dana is it a 60 or 70?

Front is Dana 60, Rear is Dana M275.

 

[Hans_ky]

So far, we are finding that all the rear springs and rear axles are the same. Interesting.

 

[BacaraTremor]

Buddies F-350 FX4 LB vs my F-250 Tremor 6.7 with required High Cap Tow package which upgrades springs and rear axle.

 

[Rock Taxi]

My 6.7l King Ranch F350 has the same numbers on the springs.

Ed

 

[2020Tremor]

This is a great thread, looks like the F-250 and F-350 Tremors do have the same rear suspension. My 11300 GVWR 7.3L F-350 also has the same PN.

 

[Mike Alcocer]

And I am sure they all have the same axle, the Dana M275. Must just be the engine choice that changes the tow capacity. But that really calls into question the high capacity tow package the diesel has that is not an option on the gas

 

[2020Tremor]

And I am sure they all have the same axle, the Dana M275. Must just be the engine choice that changes the tow capacity. But that really calls into question the high capacity tow package the diesel has that is not an option on the gas

I am speculating here but believe the big part of the diesel high capacity tow package is increased GVWR to 10800. It appears the diesel is around 800LBS Heavier than the 7.3L and wold really suffer on towing capacity assuming just a 15% pin weight. For example the heavily equipped Lariat 250 7.3L Tremor I test drove had a payload of 2783, 10000 GVWR, and the a near twin diesel had payload of 2782 ,10800 GVWR. Assuming a 150LB driver both would max out at about 17,500 LB towing capacity due to payload. Since the gaser has only a 2600 GVWC we have to adjust the max towing down to around 16,200 to stay at 2600 GVWC at a 15% pin weight. A lesser optioned truck would be required to achieve what Ford is publishing for max. Without the HCTTP, payload Of 800LB less would limit the max towing to a measly 12,200 at 15% pin weight. The HCTTP is most likely not offered on the gas since with 4:30 gears it is very close in max towing of the HCTTP. I also wonder if the lighter 7.3L engine is why the conventional towing is limited to 15K beyond only getting the 2.5” receiver. I suspect there may not be enough weight up front with the 7.3L to keep from getting too light on the front axle from heavier tongue weights when towing conventional.