I purchased a set of springs from a salvage yard that were described to me as "T code" weight rating. I wanted to raise the front of the Ex off the bumpstops but not high enough to have to change anything in the rear. According to the research I did on this topic, the T code only had a few hundred pound increase in their rating and I would only gain an inch or so of clearance over my worn out B code springs.





During removal of the old springs, I noticed that my stock springs lacked the 1/2 inch thick 3rd leaf/helper on the bottom so that was going to gain me 1/2 of an inch right there. I had one blown shock, so I replaced both with longer shocks for an F250.



After wrapping up the swap, I gained 3+ inches of ride height between the axle and frame and as you can see in the pic, the tail of the Ex is now hanging pretty low compared to the front.
My wheel arch to tire gap is 10 7/8 inches in the front and 8 1/2 inches in the rear.





I have the VIN number of the donor truck and I looked up the build sheet on etis.ford.com and I see it was a 2000 F250 with the same 5.4L that I have. It does have a camper package, but I wouldn't think that would change the front spring rate too much if anything. My thinking is that either the prior owner swapped some X codes in the truck or the salvage yard pulled the springs from another truck and mislabeled them.




What should I do next? What is a good option for raising the rear on a low budget? I do plan to install a plow on the front this fall, but that isn't a long term solution. The Ex currently has G code springs in the rear with the forward facing axle wrap prevention leaf and 2 inch factory blocks.

 

If all you want to do is increase the ride height for the lowest cost then a taller block is viable solution.

If you want to increase your suspension travel and ride height without increasing the spring rate then use the longer main springs of a f250 and add descending length leafs from your old pack to build a 420 in lb spring pack. ( stock excursion rear is 420 , f250 is 330 )

You can use a spring calculator to figure out each leafs spring rate.
Handy calculator here
http://www.suspensionmaxx.com/tech-s...ng-calculator/

 

I heard that the rear springs from a F250 or F350 are of a progressive rate and the ones on the Ex are not. Would this have an effect on the calculations for spring rate?

 

What makes the truck spring progressive is they use a secondary spring.

In this pic , the very top spring Only adds rate when it contacts the landing pad on the frame. So it is "progressive" You need to remove this leaf.

The bottom over load spring spring adds rate when the pack is compressed flat,
( flat is the end of your travel )

Some People that are modifying truck springs use the bottom overload spring as a spacer for a bit more ride height.

 

I am thinking the modded B codes would be a good option.
Would it be best to stick with the 2 inch factory block, or add 3 1/2 inch tapered blocks?
Factory U-Bolts are 11 inches long. How thick would the modded B pack be?
When I pickup new u-bolts, I would want to get them long enough so that I could move to a taller block if necessary.

 

Subscribing this is post and adding a question.

I have a 2003 Ex 2WD. I have found a 99 F350 4x4 donor truck. Would anybody know if the the 99 to 03 is a good fit up. I have search the thread and internet and from what I can tell, they should fit up. I still have not been able to find a good 2wd donor for the front springs. Anybody know a good place to order the front SD springs?

 

You might want to read some of the threads on lifting the 2wd. I think a few guys have done a small lift using stock truck coil springs. Seems most buy the kit so the can get more lift and a usable geometry.

 

What exactly are you planning to do?
2WD to 4X4 conversion or lifting the 2WD?

 

B codes are rear springs, not front springs, so you were comparing stats from a rear leaf spring to the stats of a front leaf spring.

Stewart

 

My factory spring code is "BG" so I assumed the first letter was the fronts and the second was the rears.

 

Daewoo is correct, in an effort to avoid confusion the V-8 powered EXs came with B code FRONTS, same letter designation as the very popular rears. I have no idea what Ford was thinking when they coded the various springs, it doesn't seem too hard to use unique lettering for each pack, were there more than 26 different springs between fronts and rears during that generation?

 

I completely missed the warning label "5.4L" and assumed it was a normal 4x4 rig like everyone else.



Just kidding, just kidding!

Sorry for the oops, thanks Tom.

Stewart

 

I should just take the B codes I took off the front, mod them and install them in the rear!

 

I just want improve the rear suspension of the Ex, no 4x4 needed here.

I tow a 8500lb travel trailer and get a lot of sag in the back. I would like to make that stiffer with the springs from the donor 99 F-350. But at the same time I don't want a huge rack from back to front. From my forum searches, I thing I'm going to start with the spring swap then see what the before and after measurements end up. From there, it looks like my best option in the 2wd would be a small lift up front to level it out.

Any thoughts on this?

 

All that I really know about the 2WD front suspensions is that they can be a challenge to increase the ride height of correctly.
Do you happen to know your EX / TT scaled axle weights? Or the actual tongue weight of the TT? Is your WD hitch properly setup with the correct size spring bars? How much higher than than the unloaded height does the front sit with the TT hitched up and WD engaged?
Air bags may be the most effective solution as they won't get you into trying to chase the front suspension to get a decent looking rake when unloaded. But it's very important to get the WD properly setup first.