Time to stir the pot... 4.56 vs 4.88.... - Drivetrain Tech - Tech Section

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Undrstm8ed
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Yep.. better than the oil filter debate that leads to virtual fistfights and deeply rooted arguments..

I had an 8.8, 3.08 stock with NO limited slip in my 93' manual trans 4.0L. Couple years back I picked up a complete matching dana35 front end and matching rear axle in typical 3.73 fashion with a Limited Slip from a 94' Ranger 4x4 donor along with the entire I/P wiring.

Recently have picked up a Std cab 94' Ranger 4x4 as a donor parts truck for the 4x4 frame and body swap. Again I have a whole other prewired dash which will need reworking to my cab. I have the entire interior with exceptions to a few things still yet to be done before completing even the interior swapping itself which I have other questions about but that's for another thread..

As I am preparing this frame for my needs and wants, boxing in the frame, among other things necessary structurally I will be forced into simultaneously at points working in the suspension and hanging axles attributes. There will be measures taken to strengthen the few weak spots in the Dana35 setup and adding the rear 8.8 truss work. While I am updating and going through them I may as well work at the gearing and ARB Air lockers front and back which leads me into a buying question based upon gearing.

4.56 or 4.88

Now before the arguments are strewn around I understand and know that on paper tire sizes arent what they say. According to nearly every calculators math i've played with so far.., 3.73 gets me some MPG back but on the 34"-35" range 4.56 will put me in basically OEM specs with the Manual trans and 4.88 would put me more into a power band of things so it seems relevant that for the 130-200 RPM's more I'll be turning. Logically if I stay 35's which for what I do, I think 37's are just really uncalled for; and I'll likely stay 35's for more than several reasons. I'm leaning towards 4.88 gears. I could at this point not care too much about doing 100mph, I'm that asshole who does 65 MPH anyway and there is an engine swap in the future.

My intentions are more a gear ratio that does a bit better in pulling without having to drop down a gear or two for that matter.

So whose swapped to 4.56 or 4.88 on here. What & Why did you pick the gearing you did, how long have you ran that setup and after said time, regrets? Do it again? Add your comments below.

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Posted: Fri Jun 29th, 2018 08:29 am

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black06xlt
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For what's it worth in my drag car I had no change in et running 4.56 and 4.88 when I switched to 5.13 I picked up 2 tenths in the 1/8 mile. But your doing something completely different. I had a friend who had a mustang with a 5 speed and 315/35/17 had 5.13 and at 70 mph was turning around 3000 rpm on the street

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Posted: Fri Jun 29th, 2018 09:13 am

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Idahome

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auto or stick?
35" tires right at home with 4.56 with a stick shift you could do 4.88
with auto I would stick 4.56
stickshift gives you more control of your gear, so you can get away with more gear like 4.88

But this is really getting picky here, the difference between 4.56 and 4.88 is not much.
Up until just recently they did not even make a 4.88 for the reverse rotation dana 35 carrier.

What engine?
stick or auto?
are you sure you will never want bigger then 35's? LOL
Is this going to be daily driven?
Why are we not talking about 5.13 ratio?

FYI the ring gear gets pretty thin at 5.13, 4.56 and 4.88 you will be fine. I use only Precision, Yukon or Ford gears sets....

Last edited on Fri Jun 29th, 2018 10:00 am by 410customs

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Posted: Sun Jul 1st, 2018 03:25 am

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Undrstm8ed
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black06xlt wrote:
For what's it worth in my drag car I had no change in et running 4.56 and 4.88 when I switched to 5.13 I picked up 2 tenths in the 1/8 mile. But your doing something completely different. I had a friend who had a mustang with a 5 speed and 315/35/17 had 5.13 and at 70 mph was turning around 3000 rpm on the street
See attached Below (way below)

410customs wrote:
auto or stick?
35" tires right at home with 4.56 with a stick shift you could do 4.88
with auto I would stick 4.56
stickshift gives you more control of your gear, so you can get away with more gear like 4.88

But this is really getting picky here, the difference between 4.56 and 4.88 is not much.
Up until just recently they did not even make a 4.88 for the reverse rotation dana 35 carrier.

What engine?
stick or auto?
are you sure you will never want bigger then 35's? LOL
Is this going to be daily driven?
Why are we not talking about 5.13 ratio?

FYI the ring gear gets pretty thin at 5.13, 4.56 and 4.88 you will be fine. I use only Precision, Yukon or Ford gears sets....
4.0L Manual, Sorry if I didn't clarify that properly. I do want the slower crawl speed to some degree, 3.73 isn't doing it and well, the 3.08 just can't. lol And I've found in my research a lot from Richmond Gears, Yukon, and G2 Actually. 12* North has some options I been padding the wallet for. And actually, the Auto does ahve more advantages over the manual trans offroad and maybe even on road wise however, to me I drive the Manual trans because literally its more fun to drive than a "slush-O-matic" to me and makes for a nice millennial anti-theft device too..

And yes 35's will be the largest I need, at least on the 2 Ranger Rigs and for the Xterra 4x which will be sharing tire size, type, wheels, even bolt patterns so the (2) Rangers at some point will be converted to 6 x 114.3 so any of the vehicles go down while on the trail or were to suffer mass tire loss. All of the spares will interchange for simplicity and ease of carrying on. Within the trio at least two vehicles will always go and both on farther expeditions opportunities will have multicarriers on both vehicles and the trailers will be dual spares. which is an additional 6 wheels and tires. I know Overkill, but you'd have to understand the logic of it and the setup. Each vehicle will be its own with a spare but since the trailers will have additional fuel capacity in a different way, the multicarriers for the trailers will be dual spares. crazy I know but.. when you see the end results and setup.. It'll be more than impressive.., Promise lol
As for daily driven, yes mostly but neither myself nor the woman drive 90MPH anywhere anyway and if we had to, we have other vehicles for that. This "Trio" of vehicles are for literally special purpose eventually. I know, seems vague but no spoilers yet and 5.13 just seems over the top even for me.

Below is some compiling of my research based upon the current tire specs, but you'll get the point.

At 65MPH RPM would be 2574 +/- (4.88) a whopping 200 RPMS less @ (4.56) should be closer to 2405 - 180 or so RPM's less.. minuscule really but the shift points, and that little bit on both ends will help between low crawl-ability and some power delivery I think. Like I said, I'm not worried about top end - wrong vehicle.

Last edited on Sun Jul 1st, 2018 03:31 am by Undrstm8ed

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Posted: Sun Jul 1st, 2018 10:05 am

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Idahome

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4.88 for you

5.13 the ring gear gets pretty skinny
With your 5 speed melinial anti theft device LOL 4.88 will work just fine. I follow your logic perfectly
and I wish my wifes FJ and my BII had the same bolt circle! That would be awesome luckily all of our polaris machines do have the same bolt circle

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Posted: Mon Jul 2nd, 2018 01:08 am

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Undrstm8ed
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410customs wrote:
4.88 for you

5.13 the ring gear gets pretty skinny
With your 5 speed melinial anti theft device LOL 4.88 will work just fine. I follow your logic perfectly
and I wish my wifes FJ and my BII had the same bolt circle! That would be awesome luckily all of our polaris machines do have the same bolt circle
Yea the price difference is within dollars or two if not penny's I just I guess looking for a bit of validation as gearing in this sense is still new territory for myself in some ways. Always seem to be able to assist others with decisions but my own...(?) its often a or get off the pot thing otherwise I'll over analyze it to death.

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Posted: Mon Jul 2nd, 2018 09:03 am

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Hawk136439
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From everything I have researched, 4.88 should be similar to running 4.10s with 32' tires (my current set up). It does great everywhere accept mpg at anything over 65. So from everything you stated I would just run 4.88s.

One other thought is why not convert the Xterra to 5x4.5 bolt pattern? That would allow more wheel options(almost every jeep) and only require you to buy one set of adapters instead of 2. Also if you plan on running trailers idk how easy it will be to find trailer hubs matching an Xterra bolt pattern.

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Posted: Mon Jul 2nd, 2018 03:49 pm

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Undrstm8ed
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Hawk136439 wrote:
From everything I have researched, 4.88 should be similar to running 4.10s with 32' tires (my current set up). It does great everywhere accept mpg at anything over 65. So from everything you stated I would just run 4.88s.

One other thought is why not convert the Xterra to 5x4.5 bolt pattern? That would allow more wheel options(almost every jeep) and only require you to buy one set of adapters instead of 2. Also if you plan on running trailers idk how easy it will be to find trailer hubs matching an Xterra bolt pattern.
Hey thanks for adding in your thoughts and confirming the 4.88 route. I am pretty well convinced the 4.88 consensus is the way to go.

Wheel options arent to big of a deal considering nearly everything I would do can be custom drilled from blanks for the most part and oddly the 2 or 3 wheels I had found and were deciding on were originally available in a 5, 6 lug & 8 lug pattern, and none fit the Ranger to start with and the Xterra setup wasn't originally going to need or use an adapter or spacer due to offset. But on the Ranger that offset would allow me the use of a spacer keeping all the wheels the same, I know it sounds weird but its a themed thought.

The other issue I haven't put into play is the front suspension of the Ranger will have the Dana35 modified for Dana44 hubs and that changes things and i nearly forgot about that thought process. One way or the other it will work out as needed. There is a method to my madness.. lol

As for the trailers, rather easy route there. One trailer will be a matching Ranger bed on a portion of the left over 2WD frame with a bed rack and drawer system and the rear axle will be swapped out for a lighter 7.5 unit. I am currently working out a solution to turn the rear pumpkin into a sort of PTO to turn an alternator or generator at some point mounting and sealing it are the current hurdles without getting into a completely sealed & waterproof alternator itself, those get expensive and require attachment to a cooling system so that is not the route to take. The existing fuel tank(s) will be kept for additional fuel and a electric fuel pump handles that lock into a storage box designs in front of the boxes themselves. Something similar will be done for the Xterra using a Frontier bed and frame setup from a donor vehicle which will already have the correct bolt pattern; just one more pair for the Ranger bed.

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Posted: Tue Jul 3rd, 2018 10:53 am

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Idahome

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Cool!

I like the look of old Ranger bed trailers, but they are heavy when compared to actual trailers of the same size
The 7.5" axle turning an alternator is very interesting idea!

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Posted: Tue Jul 3rd, 2018 11:16 am

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Scrambler82
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I didn't read all of the posts but did notice 410's post.

His questions are well asked... AUTO or STICK... biggy !

I run 33" tires with a 5-sp and 4.56 gears, sometimes I wish I had 4.88's.
There are just a few times I wish I had that little more power to get up the hill and although ET may not change with a gear change from 4.56 to 4.88 when you are going from 3.23's the difference may make a big deal for the doing it.

If I had an auto the 4.56s would have worked ok better because of the automatic and torque multiplication.
If I happen, for some reason go to 35" tire. I'm screwed, 4.88 would have worked with 35" tire and 33" tire but 4.56 and 35"... almost NOT !

As stated above in a few of the posts I did glance over, know how you want to drive the drive, where you might be going in the future, future tire size chance, etc, get the data together and make an educated "guess" !

What differential will you be using ?

Ltr

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Posted: Wed Jul 4th, 2018 04:05 am

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Undrstm8ed
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Unless Sciatic nerve damage or loss of my lower extremities causes me not to.. Always a manual lol

And for now I'll be using the Borg & Warner 1354..

When I get done with my own motor swap, NP205 transfer case and an mid 80's F250 manual trans mated to 4BTa Cummins. Already have the NP205, a line up on the 4BTa locally, and the trans may end up being ordered new/reman if I cant find one of my own and I'll likely have my buddy at Liberty Gears run through it regardless.

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Posted: Mon Nov 19th, 2018 11:38 pm

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Eddie Money
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Thanks for the link. I think we are headed in similar directions with our rangers. I would prefer the 5speed, but I do lots of city driving so a manual is out for me. I think 4:88 is what I'd use for how you use your ranger. If it's too tall a you can always go up in tire. If you go 4:56 and it's not enough, going down in tire size does not help for your purposes.

Definitely interested in seeing you project. Hope it's still on track.

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Posted: Tue Nov 20th, 2018 12:29 am

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Undrstm8ed
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Eddie Money wrote:
Thanks for the link. I think we are headed in similar directions with our rangers. I would prefer the 5speed, but I do lots of city driving so a manual is out for me. I think 4:88 is what I'd use for how you use your ranger. If it's too tall a you can always go up in tire. If you go 4:56 and it's not enough, going down in tire size does not help for your purposes.

Definitely interested in seeing you project. Hope it's still on track.
Agreed on all points made..

Everything still on track, my triple, part time, self-employment, is changing this month to a dual mode and more than a 1/3rd of income increase.. Been paying down that last $16k to be in less than the next 6 mos on the 5th wheel trailer and small fires around the home front along with some family losses on the better-half's side and some smaller projects; so work load was increased and just been bankrolling thick checks in. December likewise and after that making the change to focus on one P/T and the business.. Should be getting some freedom so I can start looking for my "dream" 100+ acre property.

Outside of that.. expect some interesting things & updates..

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410customs

Posted: Tue Nov 20th, 2018 10:58 am

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Scrambler82
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Undrstm8ed wrote:
Unless Sciatic nerve damage or loss of my lower extremities causes me not to.. Always a manual lol

And for now I'll be using the Borg & Warner 1354..

When I get done with my own motor swap, NP205 transfer case and an mid 80's F250 manual trans mated to 4BTa Cummins. Already have the NP205, a line up on the 4BTa locally, and the trans may end up being ordered new/reman if I cant find one of my own and I'll likely have my buddy at Liberty Gears run through it regardless.
4">Undrstm8ed,

I was just re-reading your post, you say you are going with a 4BT Cummins, it should be nice BUT the NP205 and the F250 Manual Trans may be too low geared for the 4BT.

I believe it has to do with the low end torque of the Diesel and the fact that the 4 BT will run out of rpms real quick. I know rpm are the way to go off-roading but the little Diesel behind the 205 and the NP435 (?) Trans, and the 4.88 gears, will be turn full rpms all the time, and to me that is not a good game to play.

An automatic will not only increase low end but will give the engine a buffer, and if the right trans, as the manual, won't over rev the 4 BT.

I WAS looking at the latest out of the box Cummins R2.8 Turbo Diesel, price was right but it was advised by both Cummins and Advanced Adapters to not use my NV4500 Manual Trans, the gears is wrong for the Diesel, my AtlasII would work OK but the Trans would be geared too low.

Just something to thing on.

Ltr

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Posted: Wed Nov 21st, 2018 10:57 am

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I have a Zf5 manual from a 460 big block in my 97 F350 with the 7.3 diesel. I have 4.10 ring and pinion gears and I went to 35" tires, so even with the 7.3 running out of RPM with the 35's I get a decent highway gear (like 2200 rpm at 65 mph)

The nice thing about a 5 speed manual behind a diesel is you can shift when you want to....

I WISH I had more OD...for long runs (Like from Colorado to Idaho) I am sitting at 3000 rpm for hours at a time...something the 7.3 does not mind, but it would be nice to have a gear splitter or aftermarket overdrive so I could do 75-80 mph and get my rpm down to like 1800...but that's a big chunk of $$$$

Last edited on Wed Nov 21st, 2018 10:58 am by 410customs

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Posted: Wed Nov 21st, 2018 11:21 am

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Scrambler82
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410customs wrote:
I have a Zf5 manual from a 460 big block in my 97 F350 with the 7.3 diesel. I have 4.10 ring and pinion gears and I went to 35" tires, so even with the 7.3 running out of RPM with the 35's I get a decent highway gear (like 2200 rpm at 65 mph)

The nice thing about a 5 speed manual behind a diesel is you can shift when you want to....

I WISH I had more OD...for long runs (Like from Colorado to Idaho) I am sitting at 3000 rpm for hours at a time...something the 7.3 does not mind, but it would be nice to have a gear splitter or aftermarket overdrive so I could do 75-80 mph and get my rpm down to like 1800...but that's a big chunk of $$$$
You know this but a lot of people don't... IF you are looking to increase the tire size on your Rig, you first need to determine what you are going to do with the Rig and what rpm range is right for the engine you have; once you can figure that out, then you can look at tire size vs rpm and determine the best gear ratio.
The best of both worlds would be a low cost Gear Splitter for smaller truck, I like that... Go through the gears, then go through them again, sounds like good driving !

With a Diesel, you need to understand that rpm's are limited BUT you have torque to carry you through, so you can go long on the gear, or other words... a higher gear ration and if it is a 4x then a good gear range in the T-Case helps off road or pulling.
That's one thing I like about the Atlas-II/4.3, a nice low gear once you are at the off road site AND I can drive in 2x front or rear, so I can tow in 2x Low... but that's another story.

I digress, IF I had a Diesel, I think a nice Allision 6 six automatic would be nice, but there are others, and I would need to find out about them before going further. I was told that with the R2.8L-Cummins, the low range of the NV4500 wouldn't work as well as some autos..., i.e. too much gear I guess.
Cost of the automatics is another thing... way too high for new stuff, rebuilt, I am not sure.

Thanks for this thread and the info put here, good stuff to think on !
Ltr

Last edited on Wed Nov 21st, 2018 11:26 am by Scrambler82

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Posted: Wed Nov 21st, 2018 11:32 am

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Scrambler82
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Undrstm8ed,
IMHO... if you are running the 4BT, the NP435 Trans, and the NP205 T/C, you should think a higher gear ratio, 4.10's or in that range... !?!
Again, off-road the T/C makes up for the higher gear ratio but on the Hy-Way/The Interstate/The FREEWAY, low gears don't work, and the Fuel Consumption with suffer too.

You guys have me thinking Diesel AGAIN !

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Posted: Fri Nov 23rd, 2018 05:14 am

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Undrstm8ed
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Scrambler82 wrote:
410customs wrote:

I have a Zf5 manual from a 460 big block in my 97 F350 with the 7.3 diesel. I have 4.10 ring and pinion gears and I went to 35" tires, so even with the 7.3 running out of RPM with the 35's I get a decent highway gear (like 2200 rpm at 65 mph)

The nice thing about a 5 speed manual behind a diesel is you can shift when you want to....

I WISH I had more OD...for long runs (Like from Colorado to Idaho) I am sitting at 3000 rpm for hours at a time...something the 7.3 does not mind, but it would be nice to have a gear splitter or aftermarket overdrive so I could do 75-80 mph and get my rpm down to like 1800...but that's a big chunk of $$$$
You know this but a lot of people don't... IF you are looking to increase the tire size on your Rig, you first need to determine what you are going to do with the Rig and what rpm range is right for the engine you have; once you can figure that out, then you can look at tire size vs rpm and determine the best gear ratio.
The best of both worlds would be a low cost Gear Splitter for smaller truck, I like that... Go through the gears, then go through them again, sounds like good driving !

With a Diesel, you need to understand that rpm's are limited BUT you have torque to carry you through, so you can go long on the gear, or other words... a higher gear ration and if it is a 4x then a good gear range in the T-Case helps off road or pulling.
That's one thing I like about the Atlas-II/4.3, a nice low gear once you are at the off road site AND I can drive in 2x front or rear, so I can tow in 2x Low... but that's another story.

I digress, IF I had a Diesel, I think a nice Allision 6 six automatic would be nice, but there are others, and I would need to find out about them before going further. I was told that with the R2.8L-Cummins, the low range of the NV4500 wouldn't work as well as some autos..., i.e. too much gear I guess.
Cost of the automatics is another thing... way too high for new stuff, rebuilt, I am not sure.

Thanks for this thread and the info put here, good stuff to think on !
Ltr

Scrambler82 wrote:
Undrstm8ed,
IMHO... if you are running the 4BT, the NP435 Trans, and the NP205 T/C, you should think a higher gear ratio, 4.10's or in that range... !?!
Again, off-road the T/C makes up for the higher gear ratio but on the Hy-Way/The Interstate/The FREEWAY, low gears don't work, and the Fuel Consumption with suffer too.

You guys have me thinking Diesel AGAIN !
For the time being, https://ford-rangers.com/view_post.php?post_id=14291 i'm pretty confident still applies for my needs.. The time for me to start taking this 4BTA down to the bare block is a couple years away now. Too many irons in the fire and I'm behind 3 maybe 4 months now on my goal of getting things done in time of Overland Expo West as it is. It was going to be a 3 vehicle display and now its a final 2 vehicle display.

As for the Cummins 4BT swap, my initial comments were based off of what others have been successful at and in use. Keeping in mind these arent based upon the stock fuel pump, turbo, governor valve-train, or power stats at all. Raising the HP & Tq for that matter will also change the behavior of how the trans and gearing work. I remember the premise also of Tq is what gets you down the track (street), Hp is how far down the track (street) it will get you.

Also, under new information and research; the Ford ZF5 Transmission will likely become mated to the 4BTa and NP205 Transfer case, NOT a NP435.

Shown below are some numbers based upon just transmissions and on 4.56 gearing. (i'll be doing 4.10 among other gears to get closer to what I want. Although I am not totally concerned about top end speeds, I don't want to be limited to 62 MPH either. If I can get what I want out of the setup, still touch near 90-105 MPH IF I HAD TO STRETCH OUT THE LEGS.. I'm happy with that. I have other vehicles for speed or towing. If I have to regear or build a custom axle(s) at some point among prepare for other concerns. It won't be a Ford Ranger anymore, it'll be just a Ranger Body on a custom chassis. Whole other issue which leads me into a 3rd project design I dont want to start on yet.

As much as I will go out of my way to indulge some criticisms or a LOL.. I'm really about building a poor-mans, capable, ALL-Terrain, type vehicle with some serious tricked out features wrapped in modern day MULTI-functionality & Purpose.., minus the .50 cal mount and turret, (Mini-guns are so much more the rage.. lmao jk). Ill get the other charts up soon.. its way late now.

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Posted: Fri Nov 23rd, 2018 10:48 am

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Idahome

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Very nice!

Nothing like a 4bt in a ranger, dude I dont care if it's "been done" its still the coolest damn setup ever. The new Cummins 2.8L repower is a good option also, its just so anemic in stock form and obviously cummins only wants to see it in old Toyotas and land cruisers where a 4 banger used to be....

When my wife kills the 60 degree 4.0L V6 DOHC VVT in her 2007 FJ cruiser we will do BT4 or the 2.8 cummins
Back where we live we might actually need an engine that will still run under water!! LMFAO

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I build custom RBV, specializing in drivetrain conversions, wiring, suspension and complete custom trucks

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Posted: Fri Nov 23rd, 2018 06:01 pm

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Eddie Money
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Cant you add the r10/r11 Borg Warner overdrive planetary and get one more gear?

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I know my crazy! Do you?
2007 Sport 4door 4x4 4.0L SOHC V6 Ranger

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