Big Blue's Transformation

[Gary Lewis]

Dane - I do think there is a lot of "suggestive reading" going on.  I've read on so many other forums what people have said about the F250 4x4's, and I find myself agreeing with them.  Then when I drive Big Blue I observe just what they said.  But, prior to that it wasn't so bad.  

Jim - I do hope you are right.  And I do believe that you are.  It makes sense that with the very limited travel that the off-road manners will be poor, and there will be many spots where the front will lose traction because of that.  And if the on-road ride is anything to judge by, the off-road ride will be bone-jarring.

Basically, I believe I need a soft, supple suspension.  That would not only give the best possible off-road traction but it would also make the trip to and fro the off-road experience much more enjoyable.  So in addition to the changes up front I'm leaning toward using air bags in back to supplement a much softer spring pack.

I've also been thinking about the sway bar.  I wonder if the weird geometry of the TTB's is why the F250 sway bar makes the front so much harsher?  And, if so, will the simple geometry of the straight axle work nicely with its sway bar?  Or is a sway bar even needed?  I'm not running one now and the only difference I noticed was a less-bad ride.

Matthew - That's a good one.  Big Blue's looks won't change that dramatically, but under the skin the rest of him sure will: D44 TTB to D60 w/SD springs & an RSK; Carburetion to SEFI; T19 to ZF5; headers hitting the frame & glass packs to stock manifolds or shorties & Magnaflows; 60A 1G to 160A 3G; Sawzalled crossmember to fully-repaired one; C2 pump and vacuum boost w/a cast iron master to Saginaw pump providing hydroboost to a system w/an F450 master; 7 leaves in the rear springs to something far less with maybe air bags to supplement; etc.

And, speaking of fully repairing the crossmember, I spoke to Scott/WelderScott at church about it today.  He runs Victor Welding in Tulsa and is apparently licensed to weld anything to anything.  I told him what the problem is and he said he'd come over when the time comes and either give me instructions or, better yet, weld the crossmember up.  And, he wants to fishplate it as well.  

[ArdWrknTrk]

I think the sway bar is just helping the inside wheel planted with such limited suspension.

Where a taller truck with softer springs would roll too much, (anti roll bar) when the off side of a 250 hits the bump stops it IS going to lift the inside wheel.
It also brings both dampers into play.
We had that discussion the other day.

Personally I think you should get Big Blue fully outfitted before deciding on a rear spring.
Air bags are great for occasional trailering or carryng a load of wet sand.
Being on the trail with a month's worth of provisions and losing an air line or tearing a bag is going to make for dangerous going.
I know I always have 7-800# in the bed. If I had softer springs it wouldn't ride level and likely wallow.

How much is your air receiver/ bumper going to weigh?
How much is an additional 19 gallons of gasoline, cantilevered past the rear axle?
How will mounting a high lift Jack and the spare up that high change the CG?

Speaking of.... you might ask Scott about welding a pressure vessel.
The guys I knew that were certified for nukes/ subs/ airframes would have a lot of knowledge to share about something like that.

[Gary Lewis]

Good point about the rear springs.  I don't know how much the rear bumper will weigh, but it'll be substantial.  Plus it'll have the spare moved back from right over the rear axle to well aft of that.

As for the gas tank, it is to be the 38 gallon unit and full the gas alone will be 240 lbs.  Add in the tank and sending unit and it'll probably be 275 lbs.

But, I don't have the bumper designed as an air tank.  Instead I plan to put a true air tank under the bed on the passenger's side.

As for ripping an air line, my plan was to get the springs to carry the normal load and I'd just use the air bags for when I'm carrying a heavy load like when I'm towing.

Anyway, good idea to wait for the on the rear springs until I get the other bits in place.  

[ArdWrknTrk]

Sorry I thought you were planning to make a tank.  
Maybe that came from one of the suggestions in the bumper/spare discussion.  ?

I honestly didn't expect you to underspring the truck and rely on bladders, but wanted you to consider what else was going on back there before pulling leaves, switching blocks, etc.. and then realizing you needed the sway bar and more spring.
 

[Gary Lewis]

Yes, I originally had planned on using the bumper as an air tank.  But those plans changed and now the plan is to use a true air tank.

Anyway, glad you said something on the rear.  Who knows how it is going to look when it starts coming together.

Oh, and with the weight of the rear bumper, spare, high-lift jack, and gas behind the axle there's less for the front springs to carry.

[ArdWrknTrk]

Gary Lewis wrote

 and with the weight of the rear bumper, spare, high-lift jack, and gas behind the axle there's less for the front springs to carry.

This is true traversing flat and level ground but going over bumps/rocks and landing is going to subject the front springs to normal weights and the winch bumper, extra battery and whatever else (like the compressor)

[Gary Lewis]

Very true.  But, as long as there's travel in the springs for that to happen then it shouldn't be a problem.

I'm anxious to see how much room there is between the spring and the bump stop when this goes together.  Anyone have a guess?

[ArdWrknTrk]

I don't think I've ever seen U-code springs installed unless they were in an Excursion.
,
No idea what kind of clearance you will have in a Bullnose with the Sky RSK.
** but 2" more than a stock F-350 (4+" more that you have now) sounds like plenty to me

[Gary Lewis]

Ok, next questions.  Steve/FoxFord33 checked out the rotors and discovered that they are already at or below the minimum thickness.  So I need new rotors.  But I've also come to the conclusion that while in there I might as well replace the calipers and pads.

So I've been doing some looking and there are a myriad of different brands, including some kits with rotors, calipers, and pads.  In addition, there are "blank" rotors, drilled rotors, slotted rotors, and drilled & slotted rotors.  I've done some reading about those different kinds, but what opinions do y'all have?  And, do you have a recommended brand?

Also, there's the question of which u-joints.  I plan to go with Spicer's non-greasable SPL u-joints, and the ones for the axles are the SPL55-RX.  But, Spicer has come out with a new blue u-joint called the SPL55-1480XC.  Amazon has the SPL55-RX at $44.25, but Bronco Graveyard has the SPL55-1480XC at $45 + shipping.  Anyone know about this new u-joint?  I'm wanting an extremely good one in places that are hard to get to, like the axles.

[ArdWrknTrk]

My opinion is that while drilled or slotted rotors allow water and mud to be wiped off with older organic/asbestos pads they don't do too much with modern ceramic or metallic pads.
**If you're evolving a lot of gas from the pads and you're not racing or have lost your gearbox on a mile long downhill, you have the wrong compound or friction material.

And all the holes 'added surface area to dissipate heat' also reduces thermal mass that could be used to absorb some heat, while providing pockets for corrosion to form.
***add link that compares real world v/s track***  https://youtu.be/EIa6_C1B6UQ
Plus they wear pads faster.

IDK about preferred brands but I stay away from Wagner because of past QC issues. (Just like Autolite plugs and MrGasket parts)
Motorcraft is always good. Raybestos seems ok as well.

As far as performance brands EBC and Brembo are good.
Akebono make good friction material too.

So that's my 2c

I don't know anything about Dana/Spicer's newer lines of U-joints.
Hopefully they are sticking to their old quality standards.

[Gary Lewis]

Jim - Pretty much my understanding on the drilled/slotted rotors as well.  Thanks.

But, I hadn't heard/read about problems with Wagners.  I do like Raybestos.  And their 66476 rotor appears to be a good one.

Still struggling on the calipers.  They want real money for re-manufactured ones, so perhaps I should pull these apart and see what shape they are in.  The pads look almost new, so perhaps the calipers are as well.

On the u-joints, I think I'll try the blue ones for the axles since they are so much fun to get out, and go with the non-coated ones for the driveshaft.

[ArdWrknTrk]

Slotted rotors can help if you're deep into mud often but sometimes the screech or ringing when coming to a stop is off-putting.

Can't you rebuild calipers yourself?
New bleed nipples, boots and seals?
I suppose if the seal surfaces or slider holes are damaged you'd need new.

Wagner:
That's just my personal experience with friction coming off pads and shoes not being properly welded together.

Once... Okay it slipped through.
Bad parts twice, sorry I'm gone.
Especially something as safety critical as brakes.

[ArdWrknTrk]

I just want to add that I'm using Motorcraft severe or super duty brake pads. (I forget which)

Long lasting, no problems with wet braking or squeal.
Don't seem to fade or eat the rotors.

I would have no hesitation recommending these to a friend or using them again.

[Nothing Special]

Gary Lewis wrote

....  As for ripping an air line, my plan was to get the springs to carry the normal load and I'd just use the air bags for when I'm carrying a heavy load like when I'm towing.

Anyway, good idea to wait for the on the rear springs until I get the other bits in place.  

As you are waiting before deciding on the rear springs this isn't at all urgent now.  But I had air helper springs (Firestone Ride-Rite) on the rear of my '95 F-150.  They were needed when I started carrying a slide-in camper with it (it was a lightweight camper, not overloading the truck when it was empty, but i think I'm glad I never had to stop at a weigh station when I was load on a family camping trip).

That gave the truck the best of two worlds, good ride on even rough roads empty with the stock 1/2 ton suspension and good stability with a tall, heavy load in the bed.  But there was a third world where they were definitely lacking and that was off-road.  They REALLY limited wheel travel.  I had them mounted so the truck hit its own bumpstops about the same place it the the stops in the air bags.  But that meant the air bags acted as limiting straps.  I think I could've got at least 6" more down travel (and probably even more than that) without the air bags.

I'm not saying your stock springs are the hot ticket.  But consider your wheel travel goals when you get around to looking at air helper springs.

[Gary Lewis]

Jim - Yes, I can rebuild them. But I was expecting "new" prices to be a bit less than the $85/ea and up that I'm finding, and thought I'd just go "new". So I will pull them apart and see what they look like. It isn't as if they are all that hard to replace at a later date if needed.

And, that kinda explains my thinking on this project. If it is extremely hard to get to, like the internals of the differential, then do it RIGHT. If it is hard to get to, like the u-joints in the axles, then do it right. If it isn't too hard to get to, like brake calipers or driveshaft, then use good quality components.

Man, that's really poor QC on Wagner's part.

Bob - I guess I hadn't thought about the air bags limiting travel. You had the stops on the air bags hitting at the same time as the truck's bump stops. But, since you need to keep some air in the bags at all times they were limiting things long before hitting the bump stops? Is that what you are saying?

So, if the air bags were set so that they came into play at minimum pressure at the same time as the axle hit the bump stops then you'd have full travel in an unloaded situation. And since the bump stops would prevent travel from going any further you'd never hit the air bag's stops. Would that work?

[ArdWrknTrk]

What I got from Bob's reply was that the airbags were acting like limit straps, keeping the suspension from fully extending.
But that's just how I read it

[Gary Lewis]

Duh!  Yes, that's what he said.  My bad!  

So they are connected to the frame and axle and don't stretch far enough to allow full travel.  That's surely what he said rather than my poor understanding.

But, that makes me wonder if all air bags work that way?  Probably, but it would be something to explore.

Thanks for the correction.

[Nothing Special]

Gary Lewis wrote

Duh!  Yes, that's what he said.  My bad!  

So they are connected to the frame and axle and don't stretch far enough to allow full travel.  That's surely what he said rather than my poor understanding.

But, that makes me wonder if all air bags work that way?  Probably, but it would be something to explore.

Thanks for the correction.

Yup, that's what I meant to be saying.

I probably could've mounted the air bags so they limited up-travel more and down travel less if I wanted to make that trade-off.  But I didn't think through it that much when I mounted them, and for the use that truck saw it was never a big enough issue to work on it.

I did consider trying to modify one side of the mount (top side or bottom side) to let the axle fall away from the air bag (or the air bag from the frame) to allow full droop.  But I would've wanted to recapture it when the axle came back up so it couldn't "squirt" out, and I never had a great idea on how to do that.  And see the paragraph above about it not being that big an issue for me.

I know that there are air springs that allow a lot more travel than the Firestones I had.  There are competition rock buggies with insane travel using air springs (geometry helps them too of course).  So I'm sure there are ways to get whatever you want to get.  But it likely won't be as simple as ordering bolt-on air helper springs and following the directions.

I think if it was me I'd skip the air bags and go sort of middle of the road with the leafs.  Maybe not as stiff as would be ideal for carrying the biggest loads I envisioned, but not as soft as I'd consider ideal for trail running.  I'm sure you could come up with something better with enough work.  But I'd be tempted to keep the work down and just strike what I hope would be a reasonable compromise.

That said, as I talked about in my trip report from Ouray last year, my '71 Bronco was one of the slowest vehicles on the trails, and ride quality was the limiting factor on my speed most of the time.  Any 3/4 ton truck will be handicapped in that way even more than my Bronco.  The minimalist approach I said I might favor would simply accept that limitation.  I still think that's what I would lean toward.  But I certainly understand the desire to improve on it.

[Gary Lewis]

Bob - Thanks for the clarification.  I'll probably continue to think about this and maybe even search for an air solution that'll give more travel.  But, doing anything about it will be at the end of the project so I'll know more about the weight, the ride, etc.  However, if anyone has any ideas, please let me know.

As for rebuilding the brake calipers, I don't think so.  That's 'cause I can't find a complete rebuild kit with pistons, and if I did it looks like it would be 2/3 the cost of a reman'd one.

Raybestos' catalog doesn't show a kit for a '95 F350 with pistons, just the seals, bushings, bolts, and springs.  But Crown Automotive has a kit, albeit not for a '95 F350, that does include the pistons, and it is $23 at Summit.  On the other hand, Summit has a Cardone reman'd caliper for $31.  

Note: I'm not saying I'm going with a Cardone unit, but even a reman'd Raybestos is only $44, so that's probably what I'll go for.  However, Raybestos has two:

Raybestos Rust Prevention Technology Brake Calipers FRC10521C: $43.99 + shipping at Summit

Raybestos Professional Grade Brake Calipers FRC10521: $44.99 at Summit, + shipping

So, why not save $2 on two calipers and get the plated ones?  

As for why I need pistons, these appear to be aluminum and are supposed to have a steel head.  But, the ones from the first caliper I looked at are in poor shape.

[ArdWrknTrk]

Aluminum is a stupid material for pistons with its heat coefficient and propensity for corrosion.

Only the bore needs to be good for them to seal

Phenolic, or titainium with a ceramic cap are good.
Even stainless would be way better than aluminum as far as heat transfer to the fluid goes.

Raybestos PG are simple but ok parts made to a price point where the shop can get a healthy markup.

If you're buying all these parts maybe you should look at Rockauto?
As long as you don't get hammered with shipping from six different warehouse locations there is money to be saved by purchasing orphaned parts.