I have a 1984 F350 crew cab 4X4 with the TTB front axle that eats the outside of the front tires. I did a Cummins swap and added an extra spring for the added weight. When it had the original 460 and now with the Cummins, it has always eat tires. Thinking about doing a solid axle swap, but can't find a Dana 60 anywhere near my hometown. Will a super duty front work, and if so, what all will need done. I know the bolt pattern is different (metric). Is the spring pad width the same? Overall width the same? I anticipate issues mating steering components. I don't know much about the TTB front or rebuilding them. Looks simple, but looks can be deceiving. My latest front end alignment cost me $488. Advice??

 

the problem is tire wear because of poor alignment or worn pivot/shakle/spring bushings ..

though all my bushings are stock and work just fine .. almost always tire wear on ttb is due to poor alignment ..

though it cannot be ruled out that the cummings motor is the problem ..

but .. the ttb isn't so bad if it's dialed in properly .. i don't/wouldn't trust anybody else other than myself to align my vehicles esp a ttb where most alignment shops haven't a clue and will set it improperly ..

i send my friends to a good (rare) alignment shop that i know of where they take my prefered camber caster and toe specifications and i ask them to specify printouts of corrected angles prior and after completion of work .. every vehicle is different to what best will suit it for drive line angles .. unfortunately with our trucks there is no appreciable camber and caster adjustments that can be made .. the exception being those 2 degree variable pitch bushings ..

that normally don't make much difference .. but with one extera spring and no modification to the inside radius of the axle pivot point .. you will have probably about 2 degrees extra positive camber .. making the outside edge of the tire the contact area as the top of the rim is angled out ..

for street driving and stability you should always seek slight negative camber .. 2-3 degrees if fine for most .. 4 if you are an agressive driver cornering and 5 if you are a speed racer .. however positive camber is better for off road traction and that's why the 4x4's have straight or maybe even 1 positive from stock .. obviously this isn't working with your spring addition .. the best thing to do would be to take out the bracket that holds your inner axle radius arms in the busings down from the crossmember area and weld support steel to enlarge the bracket and re drill the pivot hole 1/2 inch higher / drop the middle pivot point down half an inch .. and fill the old hole with weld .. though this isn't possible for most diy folks and requires a bit of extra calculation to get it exact .. but you could get any nice negative camber you'd like this way ..

eventually .. not in a hurry .. will do a real lift and cut weld and drill my brackets and adjust springs and shackles .. and all that but like i said i'm fine for now with just 35's and the stock springs .. ideal .. no .. but it's okay .. as it is there is no great way to make major adjustments to either the camber or castor .. though when i do this i will also ajust some good degree of castor into the mix .. maybe 5-7 degrees .. it's set at practacly zero .. adding castor makes the wheels track straight at speed though can exibite toe out on turns and slight more effort in parking lot situation s.. but i prefer solid effectual road control and comfort to parking lot or crawl situations as this is most common .. this is just setup for 4x4 and making adjustments isn't a simple thing unfortunatly ..

sorry if i'm not answering your response about the sas and super duty info because i don't know .. just helping to understand why what you have isn't working .. and also to defend the ttb .. it can be made to perform decently for what it is and i like it enough despite it's shortcomings .. a solid axle isn't a high tech super solution either .. but it will negate deflection which is exaserbated by other poor alignment issues ..

long and short of it .. is this .. if you'r toe is perfect .. than crappy camber and castor doesn't matter .. it will track straight and it WILL NOT wear your tires .. it won't corner super comfortably or track at speed or be nice with a stiffer positive camber and no castor but it won't wear tires unless you do not have you alignment set properly ..

i don't trust any shop ever to set my toe .. this is the most critical and this is your problem .. did they gold plate your ball joints too? wow .. but your 488$ alignment is not right .. you really need to .. or i would suggest you should do this yourself for 0$ and it'll be much better ..

start off on perfectly flat surface .. straighten the driver wheel while in motion .. creep 2-3 feet and don't bind the wheels let it be a natural center .. it may take a few creeps till the wheel is centered then get out and look down the front wheels .. look at the tires on the front wheel front side furthest sticking out to back side furthest sticking out .. and it should point directly inline with the back tires front edge .. if you have bad camber look in the middle portion so the angle doesn't throw you off .. do this with both sides getting them to point as nearly perfectly to the back tires as possible .. then get some wood or steel bar and attach them to the front tires and measure the distance from the back of the wheel at the straight edge and the front of the straight edge span .. to compensate for wear and slack in the steering you want the front about 1/4 inch shorter than the back so that when at speed you will experience zero toe ..

once you have got it as perfect as possible while stationary .. mark the tie rods with paint or something so you have a refrence and take it for a spin .. if it pulls or tracks one way or the other or the wheel isn't straight stop and make an adjustment .. just think about how it's acting and make the adjustments every time you stop and remember how many turns you make on each side and if it improves work from there if it gets worse stop and return to the last position or reverse it .. return to the refrence marks if needed ..

i also have some 1/2 steel plate x4 and 4x chrome in inch rod that i use sandwiched under my front wheels so i can make adjustments without moving to slacken the steering after each stationary adjustment .. but creaping the truck a few feet will also unbind it .. and also do this and look visually as you road test ..

it takes me pretty much a good afternoon to dial it in perfectly .. but i wear NO tires as 35 inch BFG's aren't growing on trees i gotta keep em in good shape ..

otherwise yes swap out an axle .. sorry if this isn't the info your looking for but i thought i'd throw in 2c .. i'd be interested in hearing about putting a super duty axle in and what all that entails .. not that i want one but it'd be interesting to know .. good luck ..

 

If I can rebuild the TTB successfully, I'd be happy. I have one in my F150 with 220,000 miles and never a problem. 40,000 plus from a set of tires. The F350 is another story. The alignment shop had it 3 days and say it's right, but a tire lasts approx. 12,000 miles. Getting expensive. I am retired, so the truck is a driver now. I'll check into rebuilding the TTB. I was told of a shop an hour away that knows TTBs. I'll be calling them. Like to do it myself, but I have a broken foot, and a failed back surgery. Kinda dead in the water for now.

As for the added weight of the Cummins, I added the extra spring to bring the front back to factory height. I replaced the spring bushings. The Cummins weighs approx. 500 lbs more than the 460 I removed. It has no lift and the tires appeared to "set right". It drove better before the alignment, but they will only align to factory specs. I asked for a specific alignment, but no go. I'm not an aggressive driver, but we live in WV where no roads are straight. All curves. I take it pretty easy in the truck. I'm in no hurry.

I'm checking on air bags for the front end now. The Cummins engines have wreaked havoc on the Dodge front end components. Heavy engine for sure.

I do appreciate all you have to say. Hard to find anyone with a true knowledge anymore. Most of the ones that I know are gone now.

Again.... THANKS!

 

That shop you have been using must be lousy. First off, you can't align any vehicle unless you check it for worn parts, they should do this before they attempt an alignment. Second, any shop you go to, take it in with the worn tire on it, show them the problem, and say that is what you want fixed. They should have a machine that will give you a readout of the alignment specs before and after. The machine should tell them right away what the problem is. Ask them if they will warranty their work and guarantee that tire will not wear like that.

Getting them to do the work will be expensive, most of the shops in my area will let me take it home and replace the parts myself, and just charge me a small setup fee for putting it on the machine. When I am done, I take it back and they charge me for the full alignment.

 

What does the camber look like? You need to check it after the truck was driven forward (it'll go more negative when you back up). But wearing the outside of the tire could be too much positive camber (the top of the tire tipped out as you look at the truck from the front). Adding a spring leaf or air bags could make that worse.

 

My 96 had a 460 in it and I added a extra leaf to the front because I thought I would need it when I put my Cummins in. I ended up taking it back out it rode to ruff, and it still rides ruff with just the original stock leafs.

 

maybe put the diesel spring for the idi truck ?

the ford diesels are heavier than the cummins so a stock spring set would likely work better than an extra leaf added to a 460 pack ..

that would get you a good stiffness and ride .. there's a feller that posts here on fte at least on the diesel site that is a spring dealer and has good quality springs new that are recommended ..

but ultimatly even if it rides rough or stiff too much spring shouldn't eat your tires .. it's just bad alignment .. almost certainly toe in by a few degrees .. i suppose the steering wheel is centered when your pointed down the road?

if so they probably set it a few degrees in - or a few degrees out - equally on each side .. this will exhibit few driving symptoms - but eating tires and some shops do it to sell tires .. i would visually look .. they're probably either both pointed in or out a few degrees ..

if they are centerline correct / but out or in on each side equally .. it is easier to fix and it might be the case .. if they're in .. adjust the tie rods out equal turns on each side out .. or vise versa .. but with the foot and back i don't know .. maybe measure and hire a backyard mechanic to hold the wrench ?

sorry to hear about the alignment shop .. but that's your problem .. there really is no camber or castor adjustment to worry about in this case ..

it could be worn pivot bushings but almost 99% sure it's only a matter of setting the toe properly .. it's a bummer about the foot and back because i hate having a shop do this .. it's really actually easy though requires alot of rolling around which in your case wouldn't be good ..

but it shouldn't take more than 100 dollars and a 3 hrs to set the toe .. and that's being very generous .. with computer equipment it should be very fast and easy and cheap ..

once when i was a kid i got a popped tire changed out .. they said ' we can do a free alighnment ' .. yea okay go for it .. then the wheel was crooked ! and it pulled ! it was fine before ..

they said they did it right .. and put it on the computer .. they did it again and it was worse !

well anyways later i worked at a place we made coats and bear ammco wheel alighnment machines .. rim clamps and sensors .. so i learned much more about it .. and really the computers aint all that great .. and if the equipment isn't good or misaligned there's another knock .. and if the tech is lazy .. stupid .. or incompetent .. or a jerk wad .. well alot can go wrong ..

i do it myself and have alot - probably way too many miles .. on old dry BFG rubber i pick up and recycle ..

 

Sorry I haven't been back for a while. I have some health issues that have had me down for a few week and still have a few weeks to go.

The shop that did the work was the largest, newest shop in town, but it's only as good as the guy running the equipment. I went back after it continued to wear the tires, but was just told "sorry". I found a shop with a good reputation for TTBs an hour away. I purchased a set of Energy Suspension pivot bushings and I'm waiting on a guy to install that. That I think will be the biggest factor. I talked to a guy at a local spring shop about it. I have a 2 leaf spring with a #3400 rating. He sells a replacement 3 leaf spring with a #4000 rating that should cover the added weight of the Cummins. He said he's dealt with the extra weight of the Cummins engines before. Hope to have everything installed in a few weeks.

After the alignment, the tires looked great for all I could tell with the naked eye, but it has continued to eat tires for the 5 years I've owned it. I have a F150 with the TTB and the tires on it now have 40,000+ miles with no abnormal wear. I know it can be done. I'll keep ya posted. THANKS!!

 

I finally got the chance to check it out and the pivot bushings were beyond bad. I had a friend stop by to help change them out to Energy Suspension polyurethane bushings. I took it for a drive and it handles so much better. The tires appear to be great when sitting on level pavement. My friend worked at an alignment shop for a few years and seems to have good knowledge of it. He suggested a certain individual at that shop do an alignment. I have an appointment for Monday morning. He told me to be sure to get a print out and he would like to see it. I haven't found a shop yet that will align to anything other than factory specs. I'll let ya know how it goes. THANKS!