Rear F code modification pics-instructions - Diesel Forum

Dunbar · 06-01-2007, 12:08 PM

I have saved several posts on using V codes and F codes but do not really understand the modification to the F codes using parts from the Ex spring pack. I know that one of the springs is cut and used along with one of the shims.

Without being able to see everything in front of me it is hard to understand which spring from the Ex is used and how it is modified.

I am about to order V&F codes from the dealer as I have not run across a bargain elsewhere. Does anyone have pics of which spring is used and how it is cut?

Thanks,

David

HEAVYHITTER · 06-01-2007, 12:51 PM

Boathauler did the F codes and took one of the stock leafs (the bottom one w/ the rubber bump stop) and cut the front of it to match the way the back looks. When you crawl under your rig you will see that the rear of that lower spring is short and stubby and the front is long and the rubber bump piece sits on it. He just cut the front to match the rear.

I hope that helps. I am getting so close to lifting and spring swapping.

Dunbar · 06-01-2007, 01:04 PM

Thanks Cminus,

That is a good enough description for me to figure it out. I will do that and install one of the .125 (I think) spacers to get the front and rear level. I would rather be rear high than front high if necessary. I do not notice my rear sagging much now when I hook onto my 6000lb boat so I should be good with it level without towing. I can always add the air bags.

David

towrig · 06-01-2007, 01:08 PM

I originally added a cut piece from the anti-wrap leaf and a thin shim. This gave me an additional 3/4 inch to go with the 3/4 the F codes give on their own. Recently, I removed the anti-wrap leaf chunk and shim and slid a leaf from the stock spring pack below the 4 leafs and above the variable rate leaf of the F code pack. I used the 3rd leaf from the bottom of the stock rear springs (not counting the anti-wrap leaf). It must be trimmed in the front a bit to fit properly, about 1/2-3/4 inch. This is the same thing boertje did with his springs. It looks like the rear may wind up a bit higher, but I haven't filled the tank yet for a true comparison.

So far, I like it better this way. It softened the ride (not as harsh) and the "wander" did not return. Unloaded, the leaves no longer sit on the variable rate leaf. I have pictures on my camera from when I did the work, but I haven't had a chance to upload them. I'll try to in the near future.

When I hit a hole or big heave in the road, the rear axle now has the same amount of "bang" as the front axle. Before I added the old Ex leaf to the F's, the rear axle hit noticably harder than the front axle.

yanvaryjt · 06-01-2007, 02:47 PM

I explain the rear spring pack modification I did to my Ex in this thread:
http://forums.thedieselstop.com/ubbthrea...rue#Post3255923

boertje · 06-02-2007, 12:34 AM

Here is the link http://photos.thedieselstop.com/show...amp;si=boertje to the way I did it. The pictures dated March 23, 2007 are with a piece of the anti wrap leaf as shim. I didn't like this method because the 4 leafs had no travel since they were bottomed out on the variable fat bottom leaf. The pics dated April 15th are using the 3rd leaf as towrig outlined above. I have driven 5300 mile cross country with this mod and it handled great. I don't think I could improve on it at this point. As you can see on the pics that the leafs don't rest on the variable leaf. There is still some travel and the ride was softer yet firm...just right. With the X fully loaded, fueled, and 5 people, the springs just barely touched the variable leaf.

Dunbar · 06-02-2007, 11:17 AM

Thanks for the pic link and the info.

I now have all the info needed to do mine. I will use the whole leaf like you guys.

I did notice in the instructions with my hellwig that the RR plate on the shock mount does not need to be removed or cut and your pics confirm that. Perhaps Hellwig changed the hardware to work with this thing at some point after others cut it or replaced it.

David

Bruce1954 · 06-02-2007, 09:09 PM

[ QUOTE ]

I did notice in the instructions with my hellwig that the RR plate on the shock mount does not need to be removed or cut and your pics confirm that. Perhaps Hellwig changed the hardware to work with this thing at some point after others cut it or replaced it.

David

[/ QUOTE ]

Just to clear things up:
As far as i know the right rear mount of 00 to 02 Xs was never a problem with the Helwig just the ford unit.

Choice for older X owners is to deal with the plate, cut or replace or deal with the helwig hardware.

Bruce

HEAVYHITTER · 06-02-2007, 11:26 PM

[ QUOTE ]

Choice for older X owners is to deal with the plate, cut or replace or deal with the helwig hardware.

Bruce

[/ QUOTE ]

[img]/ubbthreads/images/graemlins/biggrin.gif[/img] It still makes me laugh thinking about how bad the hardware kit that was shipped with mine was.

Pharmer · 06-04-2007, 02:45 PM

I have similar issues and wondered if the Edelbrock's are the best shock now that I have changed the springs to U and F.

I see you have Rancho 9000 shocks, how many miles on shocks? What tire pressure are you running? You mention the improved ride with the extra leaf, is that because prior to this the springs were bottoming out on the variable leaf. I saved the last two leafs and the anti-wrap from the old springs, but will adjust tire pressure and maybe go to newer shocks first.

With regards to the front springs: On my 2000(V10) with the U-codes I changed the front shocks to F-350 application using the Monroe reflex and this helped a great deal.

towrig · 06-08-2007, 01:20 AM

I have around 10K miles on the 9000's. I'm on my second set due to the adjusters seizing after two winters (thank you Western New york salt trucks). I liked being able to adjust them, but since the spring change, I set them around 2-3 and left them. If I get a big trailer behind me again I would turn them up. Mostly, I was trying to fix the wander problem with a stiff shock. It didn't work. It seems like any shock is an improvement over stock.

After the spring change, I'm able to run 50 psi in the front and 55 in the back. This is much better than the 70/80 I was running to help cut down on the wander.

I believe the ride is improved because the spring isn't sitting on the variable rate leaf anymore. The front side was sitting on the variable rate leaf (follow link in sig to pics). There isn't a huge gap there now, but the vehicle can definitely travel before engaging the variable rate leaf.

Pharmer · 06-08-2007, 05:16 PM

I hear you on the salt, we also mix it with sand in Northern Michigan. I found that alot of noise from the rear of the vehicle over bumps was the from the headliner. I dropped the headliner down over the cargo and 3rd seat area and found that the crossmembers bang on the roof panel. I sprayed some foam insulation between the roof panel and cross members and insulated the between the headliner and roof panel. Much quieter over bumps now.

Same as I did on the tire pressures. I'm not sure what Ford recommends on the E rated now, the sticker behind fuel door still had D rated pressures at 50 and I think 55 for the rears.

I do have Timbrens for the front from my old Ex. which I may try on the front again.