SaltEater

So as part of the final build for my truck ('93 xlt 4x4, 5.8l, e40d), I'd like to run 35" tires. In prep for that I'd like to regear to a 4.56 ratio and if i'm tearing down the front end that far I may as well replace/upgrade everything from the diff out to the hubs anyways right?

So here's a tentative parts list from rockauto (nothing is ordered yet), let me know if I'm missing anything or if there's a better part out there.

• 3.92+ open carrier case - USA STANDARD GEAR USA20116
• Diff overhaul kit (Koyo bearings) - USA STANDARD GEAR ZKD44IFSL
• 4.56 Ring + Pinion - DANA 2020499
• Cork Diff Gasket - MAHLE P27768TC
• Axle shaft seals - National Left and Right
• Axle shaft bearings - Timken inner and right?
• Axle U-Joints - DANA 5760X
• Driveshaft u-joint - MOOG 264
• Wheel seals (inner?) - NATIONAL 4250
• Wheel bearing inner - TIMKEN SET37
• Wheel bearing outer - TIMKEN SET45
• Spindle Hub Seal inner - NATIONAL 710453
• Spindle Hub Seal outer - NATIONAL 710455

Some notes:

I'm not interested in an SAS just yet, though a d50 third member swap could happen if I can find one before I have the parts ordered. I do plan to drill/tap for a magnetic oil plug and might do the clip elimination.

I'm not super sure I have the correct axle seals/bearings selected, seems to be a difference between left/right axle shaft thickness? I know in fwd cars they'll do that to offset torque-steer caused by different length axle shafts... Seems to me there should be an outer wheel seal in there somewhere.

The wheel bearings I've chosen for some reason have "manual trans" in the title, but I fail to see how that would matter, even manual/auto hubs should still have the same bearings? Also need to find some spindle bearings somewhere.

I had to go into the bronco section to find the high end spicer u-joints, is there any reason they'd be there and not in the f150 section, are they actually a different size? I couldn't find any heavy duty spicer non greasable driveshaft joints, so I guess moog for now.

Any special tools a guy should pick up? I know i'll need the correct spindle nut socket, a dial indicator, and probably a bearing puller and seal driver.

[edit: changed to 4.56 gears]
[2nd edit: All parts ordered and on route. Also through in a lunchbox locker for the front, and will be getting a detroit for the back]

Steve83

I can't agree with that logic. If it's not on the maintenance schedule, and it's not broken or otherwise unusable (for my purposes), I'd leave it alone.

As to the parts: I prefer Made in USA or Ford/MotorCraft whenever possible. I commonly collect used Ford parts in the JY, clean & reuse them - they last. When I can't find what I need, I shop Amazon, eBay, RockAuto, LMC Truck, BroncoGraveyard, online & local Ford dealerships for genuine MotorCraft parts. If I still can't find it, or it's too expensive, then I start considering aftermarket imports. So I'd avoid that overhaul kit with import bearings. And I'd check the other parts' sources before assuming they're made here just because of the brand name.

Since you have no information about your truck in your signature, I can't say if any of those are the right parts. Click this & read the caption:


(phone app link)

There were MANY variations in the '80-96 D44IFS, and some would affect your parts list. Do you have the axle BOM?


(phone app link)

This album has my drain plug & C-clip eliminator:


(phone app link)

This album shows how to rebuild the hubs, wheel bearings, & brakes:


(phone app link)

This TSB discusses U-joints. If they're the same size, they'll fit regardless of what vehicle they're listed for.


(phone app link)

Setting up new gears is not a shadetree job - it takes skill, experience, the right tools, & the knowledge of how to use them. I have them, and I've rebuilt a few professionally, and I still wouldn't build my own. It's worth it to me to pay someone local with a LOT more experience than I have, who can do it quicker & probably better for a reasonable amount of money. Sometimes the bearings have to be pressed on & off several times to adjust the gear mesh, so if you're working with cheap tools (tools that you can afford if you only plan to do the job once), you'll lose patience & fingers before you get it right. And when you find that guy, he'll probably do the entire third-member job (including finding the best bearings & seals) for about the same price as setting up only the gears for you.

As to the choice of gears...
I can't imagine wanting gears that low & weak. They'll apply more torque to the tires, but the pinion gear gets so small for that ratio that it's easy to bend or break under those loads. And the road speed will die miserably. I run 33s with my truck's stock 3.08 (3.07 front) gears, a little 4.9L, and a non-OD stick. I can pull a stuck cement truck out in Low Range 1st, and I can get a 3-digit speeding ticket. I'll never regear it.

SaltEater

Oh whoops, I entered that into the profile dealy but i guess that doesn't make it show up on posts. The truck is a '93 4x4 xlt, 5.8l, e40d.

Current axle gears are 3.55 open (on 31's), push button 4x4. It's dumping freezing rain outside now, or i'd go have a peak underneath for the axle tag. Door sticker says 19. I am almost certain the middle u-joint is frozen, so i'd have to pull it all apart anyways.

Don't learn anything if you don't do it yourself, though for regearing i might drop it off somewhere. You may be right about the 4.88's being miserable though, 4.56 may be a better choice.

I used Rockauto because you can save multiple carts, i'll cross reference on amazon and ebay, but I'm in Canada and Rockauto somehow manages to beat most everyone (even with conversion + shipping) for the things that i've looked for so far. I'm really more concerned that I'm forgetting a type of part rather than actual part numbers though.

I'm mostly planning the gear choice for 2500 rpm which is where I think peak torque is going to end up when I'm done with an engine rebuild.

And lmao off at that 6.6:1 1st gear ratio (and 8.2:1 rev?! wtf). Little bit of a difference from the e4od.

Steve83

An OD slushbox actually has a wider range than my stickshift, though, due to the torque converter lowering the effective 1st gear ratio, and the OD above my 4th. So you don't actually need such low axle gears. Just good fluid (MotorCraft MerconV), the biggest trans cooler, & an inline filter.


(phone app link)

Peak torque is close to peak RPMs, for all these engines.

I like learning, too. But I still pay a surgeon, a machinist, and a lawyer. I could learn each of those, but it's just not worth the time, as little as I'd use those skills. The front diff isn't as critical since you aren't driving on it for hours at highway speeds. If the rear is built wrong, it can lock, causing loss of control, among other excitement. So if you're determined to try it, the front is definitely the one to learn on.

Your truck info may be in your profile, but it has to be in your signature for it to automatically appear with each of your posts.

'93 is when the most-significant changes were occurring in the D44IFS, so double-check your parts. Particularly wheel seals & spindle parts.

SaltEater

Well I put some stuff in my sig, prob not as much you'd like, lol. I did go take a peak at the front axle now thats -20 and snowing instead of raining, no sticker or tags, 5 screw auto hub.

If I understand what you're saying, the torque multiplication from the converter before stall makes up for gearing? Afaik, my truck still has the stock converter, so would i then be served better by getting a different converter? I plan to do an aux trans cooler and remote filter at some point anyways. Interesting to think about, but not sure how that would work out when I get around to the engine (h/c/i/e).

Do you mean peak hp is close to peak rpm? Peak torque on a stock engine is like 2000-2200, which is about the stall speed on the converter, right?

I do know that moving from the stock ~29" tires to 31's that are on it now has affected take off and general acceleration. I can only imagine what it would end up like with 35" tires. To get the same final drive as the stock ~29's with 35" tires, i'd need a 4.28 axle gear, so 4.56 seems best (i think the 4.88 stemmed from considering 37"+ tires). Just for fun I checked your setup against stock, according to the gear ratio calc you'd only be running ~160 rpm higher than stock at 75 mph.

Seems like you've rebuilt your front end enough times to know, are the axle shafts a different thickness to make up for the length difference of the offset diff?

Steve83

Yes, that's my understanding of what a TC does. I've read in many magazine articles that it creates "torque multiplication" equivalent to or BETTER than the granny gear in my NP435. And it works that way at all RPMs (below stall), where my engine's torque drops off. And it works that way through shifting, where I have to declutch & lose all torque.I don't think so. As I said: if it's not on the maintenance schedule, and it ain't broke...The cooler & filter should have no impact on the engine, or maintaining it.This is just the first thing I found on Google Images: (blue is stock, and torque is above hp)


IDK how high you rev your engine, but I never take my I6 above 3500RPM. I know V8s will go a little higher, but I don't like the sound of a 5.8L above 4K; rarely above 3500. So that's what I meant: torque peaks near the highest RPM I'd expect anyone to use in normal driving. These aren't dragsters or street-outlaw trucks.IDK what the stock stall speed is. I only recently got a slushbox (E4OD in my '93 project), and I've never felt a need to dig that deep into how it works. I like stock because it's reliable & maintainable.Naturally. But is it still "enough"? You're going to have to give up something when you make a change. Ford engineers know a LOT more about this than you or I ever will, and they calculated that this was the best setup for the market they were selling to. So my opinion is that anything else will be somewhat worse in some way. I'm willing to accept the reduction in tire-roasting ability of my little 6-cyl (BWAHAHAHAHAHA!!!!) for the gain in top speed. With a 2-speed transfer case, I can get that low-speed grunt back when I need it (towing, crawling).

But here's another important consideration for '92-96 trucks: did you recalibrate the PSOM for the current tires? If not, you can probably get back MOST of what you're missing with a paperclip & a few minutes. Read this caption:


(phone app link)That was a factory option for the heavy Fs. But they had different emissions requirements, which allowed different tuning of their engines for different torque curves & ranges. You'd probably love the 0-5mph torque & time, but I bet you'd hate the lack of top-end, and the drop in MPG.

And with 4WD, you can't just regear one diff. If you plan to use 4WD, you have to regear both. Then what happens if you don't like it? The truck is effectively totalled because you'd have to spend all that money again to go back to a more-streetable ratio. That's why I suggest you leave the gears alone for now, and see how much you can tweak it WITHOUT that down-time & expense. There's not much repeated labor or parts if you eventually decide you just HAVE to regear later.I'm not sure what you mean. All 1/2-ton D44IFSs have the same axle-lengths (per side). I've never noticed a difference side-to-side or year-to-year in axleshaft diameter among all the D44IFSs I've worked on. The D44IFS-HD probably has thicker shafts, but it's old & rare. The D50IFS has a different pivot length, which might affect axleshaft lengths.

SaltEater

Well looks like we're both wrong, stock peaks seem to be 310 lb/ft @ 2800, 200hp @ 3800. The article your graph is from states that's a stock '92 f150 engine w/ an edelbrock rpm intake and holley carb.

Oh, i know i have to give something up, that something is more than likely going to be fuel economy. There are zero emissions requirements where I am (for now, too many farmers), so I don't have to worry about parts (CARB #'s) so much when I do the engine rebuild. I plan to keep the egr and maybe the cats though. The more I read into it, the more likely I think I'm going to have to do something with the TC and trans after the engine rebuild (not the the aux cooler and filter).


From what i've been able to find out about stock e4od torque converters, the actual multiplication isn't all that much, somewhere between 1.25 and 2.5. I haven't found a reliable source to say what it starts at, but it goes down the closer you get to stall rpm. The more you stall it out though, the more you risk cooking the converter. And theres only so much torque the stock e4od can handle, i'll have to go pore through some powerstroke forums to find out what kind of upgrades there are for it. In 3rd and OD i think it locks up anyways, so better mileage, no torque.

Interestingly enough, the gear ratio calc is showing 75.9 mph for 35" tires and 4.56 gears at 2360 rpm. I never did reset the revs per mile on the psom; I read somewhere (prob here) that once it hits its 5th reset it locks out and can't be reset anymore without buying a new one.

What I mean about the axleshafts is the total length from the diff to the wheels is longer on the right side. In my fwd car, if I mat it at 10mph or less the front end will dive down and to the right because the unequal length allows the longer side to twist more before power gets to the ground. Some manufacturers (honda?) use different diameter axles (and other strategies) to combat the torque steer. That article goes on to say that an intermediate shaft can correct the problem but doesn't say how or why, driveline angle i guess?

If you say the shaft diameters are the same side to side then I need to re-examine some of the seals and bearings, would probably be best to get them from a local parts store anyway.

Though it seems even napa canada is showing different inside diameters (but the same diameters per part as rockauto) for the front left/right axle seals so i don't know. Another reason to go with rockauto, they want 10 bucks for that national seal while napa wants 28 for their house brand (which is all they list).

BLDTruth

Parts list looks solid. I just did this on my front end when I swapped in 4.10 gears.

I can't really see any reason why you would need even 4.56 gears, let alone 4.88. 4.10 gears would put you at around 2000 rpms at 75 mph. And you have a 351 so low end torque is not going to be a problem.

If you can get of one of the tools that threads onto the spindle itself and allows you attach a slide hammer - get it. If the spindles haven't been pulled before it will be the hardest part to do unless you have that puller.

SaltEater

I'd rather end up with more gearing than less gearing. Lol at the stick guys with their low 1st gears coming' in here question' my intended gears.

You're running 32" tires right? How you liking the 4.10's so far?

And cheers on the puller.

BLDTruth

Haha fair enough. It does make it easier to choose the 4.10s when you have a 3.90:1 first gear.

The rear 4.10 set actually isn't in yet. My buddy and I are going to do it this weekend. I will report back!