Rear brake upgrade

[j.whitbread]

When I see the 08 vs. the 07 rear brakes, I wonder how difficult it would be to upgrade. If both the axles are Dana 60's, it may be a matter of parts.

There's no doubt the van could use more braking power in the rear, especially when backing down hills. I understand the proportioning valve has something to do with the lack of braking. Can this be overcome?

Any ideas?

[carringb]

I'm not sure about the compatibility of the new calipers.

You do not have a traditional proportioning valve. Brake proportioning is electronic through the ABS system. I do not know how the logic determines proportion in reverse.

My rear axle weighs in at 7800 pound when loaded, and I have had to stop a combined weight of 25,000 pounds without trailer brakes. My rear brakes are more than adequate. They are the same calipers you have. However I do have slotted rotors.

I'm guessing maybe your pads were replaced at one time with an inferior pad, or have been glazed. Glazing that won't go away is usually from brake fluid contamination.

I would recommend new Ford/Motorcraft premium pads, or NAPA gold. I would recommend not using a ceramic pad as these typically have less friction unless really hot. There are some aftermarket performance pads that are better than OEM, but it's really hard to figure out the right one since the coefficient of friction of various pads is not published.

The stock E350 van brakes pads are the same used on dually cutaways up to 12,500 GVWR.

[Stumpalump]

The proportioning valve is designed to put more break line pressure to the front then the rear. A lot goes into the math like vehicle weight size of calipers and rotors, master cylinder ect. As soon as you load it down and add bigger tires the math goes out the window. On my Jeep Cherokee I gut the proportioning valve to make it a 50/50 split but thats because I run a heavy wheel tire combo and swaped rear axle to a disk break rear end. I have perfect breaks under most conditions. You can feel the rear grab on the road a little but it's wonderfull and perfect off road. To start messing with a 10k lb vehicle then I don't think it's wise unless you swap to stock newer breaks and the proportioning valve that goes with it. My opinion based on weeks of fooling with these things on other vehicles.
The biggest problem with Ford breaks is with the cheap break fluid and/or the way the Fords wear out the break fluid. First thing that should be done is to bleed out al the old fluid and start with fresh. Some of the chain auto parts stores stock Valvolene dot 3/4 semi synthetic break fluid. I'd bleed it very well or use up most of a quart to do it and see if thats a big enough help. Auto zone stocks Carbon metalic break pads that also help on long hard stops but cheap pads are better for slow speed feel like when going off road when not much heat is generated.

[saline]

Am I wrong or would braided brake lines help out? The rubber lines expand, reducing the effectiveness of the pedal pressure that is applied.

[scatter]

Besides all the comments above, I believe you'll need 17" wheels to fit over the '08 brakes. Also might want to check out your insurance policy when messing with brakes. Most will be void if the system is not stock.

[carringb]

Originally Posted by Stumpalump

The proportioning valve is designed to put more break line pressure to the front then the rear.

There is no proportioning valve on the E-series. Hasn't been since like 1989. It is all electronic brake biasing now.

[carringb]

Originally Posted by saline

Am I wrong or would braided brake lines help out? The rubber lines expand, reducing the effectiveness of the pedal pressure that is applied.

Brained lines may make for a firmer pedal feel, and may reduce travel, but it will not reduce the force applied at the brake pedal.

[carringb]

Originally Posted by scatter

Besides all the comments above, I believe you'll need 17" wheels to fit over the '08 brakes. Also might want to check out your insurance policy when messing with brakes. Most will be void if the system is not stock.

Newer E-series still use 16". It's the vans with a 4x4 conversion that need 17" because of the even larger front brakes on the newer F-series axle.

Yeah, I had a policy at one point that had an exclusion for any suspension modifications. My current policy though Allstate does not have any such exclusions. Anyone with a Sportsmobile should closely examine the fine print on their policy.

[SheepShagger]

Originally Posted by j.whitbread

When I see the 08 vs. the 07 rear brakes, I wonder how difficult it would be to upgrade. If both the axles are Dana 60's, it may be a matter of parts.

There's no doubt the van could use more braking power in the rear, especially when backing down hills. I understand the proportioning valve has something to do with the lack of braking. Can this be overcome?

Any ideas?

I have been trying to find out the same info, what parts are needed and how hard it is etc.
But IMO it's a very bad idea to just upgrade the rear. Do the front or all 4. Depending on the weight distribution of the vehicle, there is as much as 80% front vs 20% rear for perfect braking, you will ALWAYS get more reliable and effective braking from the front vs the rear which is why you never find a stock vehicle with anything even close to 50/50 on the brake bias. If you come even close to 50/50, it's very unstable braking at speed, since it's so easy to lock the rear vs front. Clever proportional brake valves will increase the rear % depending on the load (usually gauged by how much sag in the rear suspension), but the Ford van doesn't have this.

[j.whitbread]

Technically the front brakes are upgraded from stock 07 E350 simply due to the front Dana 60, hence the 17 inch wheels to accommodate the bigger brakes.

I'll have to find a Ford dealer willing to sit down and go over parts. Maybe an 07 E450 would work better than the 08 parts. It will take some homework.