Question for F350 4x4 owners

12clip

Registered User
Joined
Aug 30, 2010
Posts
25
Reaction score
0
Location
Warren MB
Just did my Dana 60 front axle swap and it went very well. I used a KP Dana 60 out of a '88 F350 that had a gas motor, possibly a 351.

I was wondering about where do a stock F350 diesel springs sit in terms of flex/sag. These gasser front leaves sit about flattened out with the weight on. I does however lift the front of the truck about 2.5" as compared to the TTB Dana 50 setup. The gas leaf springs measure about 1.5" thick at the middle of the 2 springs and taper down to about 5/8" near the end.
 

Diesel_brad

Dunce
Joined
Nov 8, 2008
Posts
6,099
Reaction score
5
Location
gilbert pa
Just did my Dana 60 front axle swap and it went very well. I used a KP Dana 60 out of a '88 F350 that had a gas motor, possibly a 351.

I was wondering about where do a stock F350 diesel springs sit in terms of flex/sag. These gasser front leaves sit about flattened out with the weight on. I does however lift the front of the truck about 2.5" as compared to the TTB Dana 50 setup. The gas leaf springs measure about 1.5" thick at the middle of the 2 springs and taper down to about 5/8" near the end.

F350 stock springs have no real arch to them. They are basiclly flat. And the thickness of the small block and the big block/diesel springs are the same. You cant tell by looking at them. The part # on the spring is the only way to tell what they are
 

12clip

Registered User
Joined
Aug 30, 2010
Posts
25
Reaction score
0
Location
Warren MB
These have a nice postive arc when unloaded as do any of the F350 springs in Dana 60 swap articles I have seen.

"i am running stock gasser front springs in mine. work great. "
Nice to hear someone else has tried this. Did you do so on purpose or is it just what you had. Does it seem to ride better than if it had Diesel springs?

I was expecting to add a leaf to the pack or put on airbags' but I will have to drive it like this first to see where I am at. I plan on putting a SKY RSK kit also.
 

Clydesdale

Full Access Member
Joined
Nov 8, 2008
Posts
1,155
Reaction score
0
Location
Nampa,Id
Apples to oranges, but Superduty levelig PSD springs ride like ass under a 460.

.75 ton IDI lift springs ride good under a 460, OR an IDI.

At least until I did my shackle flip in the ****, now the front feels like a brick, and the back feels like a Cattlerac
 

DragRag

Registered User
Joined
Aug 8, 2008
Posts
2,031
Reaction score
2
Location
Los Angeles, California
Just did my Dana 60 front axle swap and it went very well. I used a KP Dana 60 out of a '88 F350 that had a gas motor, possibly a 351.

I was wondering about where do a stock F350 diesel springs sit in terms of flex/sag. These Gasser front leaves sit about flattened out with the weight on. I does however lift the front of the truck about 2.5" as compared to the TTB Dana 50 setup. The gas leaf springs measure about 1.5" thick at the middle of the 2 springs and taper down to about 5/8" near the end.

Sounds like you are sitting about right to me. If you want the back to be more level with the front switch to a F250 block between the axle and spring in the rear. Doing that will bring it down an inch in the rear.
 

12clip

Registered User
Joined
Aug 30, 2010
Posts
25
Reaction score
0
Location
Warren MB
I will be putting a SKY RSK in the front so the rear will need to go up at that point.

It currently sits pretty level and still has the 250 block in the rear. I also have the 350 blocks at my disposal.
 

gonecrazyi

Full Access Member
Joined
Aug 27, 2008
Posts
3,276
Reaction score
3
Location
florida
When I put in my dana 60 I left the f250 blocks and it sat a bull dog but sagged to much when I put the trailer on it. So I tossed the 350 blocks in to fix the problem. Overall I gained 2.5-3 inches in the front which gave it a much nicer look.
 

12clip

Registered User
Joined
Aug 30, 2010
Posts
25
Reaction score
0
Location
Warren MB
So can anyone else comment if their springs sit flat or still have a bit of positive arc when loaded?
 

Dieselcrawler

Professional wrench holder
Staff member
Joined
Jun 4, 2010
Posts
5,292
Reaction score
650
Location
Quakertown Pa
mine rode great when i had them springs in. no sag. but i hat the rake to the front, to i put AAL in the front to level it out.
 

BigRigTech

Diesel junky
Joined
Feb 10, 2007
Posts
3,288
Reaction score
2
Location
Nova Scotia, Canada
I had 351W gasser springs under my diesel when I did the swap - worked just fine. The springs were pretty much dead straight. The springs in my F350 are custom 2 leaf springs - really thick. I don't know if they will fit but cab and chassis F350 front springs are atleast twice as thick as reg F350 4x4 springs from what I've seen.
 

12clip

Registered User
Joined
Aug 30, 2010
Posts
25
Reaction score
0
Location
Warren MB
If anyone has a positive arch front spring, they have either re-arched or non-stock lift springs.

How can this be if most people are saying that their springs end up flat with the weight on them. They must have started out something higher than flat with out being compressed by the weight.
 
Top