Ford 8.8 with 7.5 axles and tubes?

[Ranger4x4newb]

I have a 98 4x4 with axle code R6. It should be a limited slip with 3.73s but I just changed theoutter bearings and seals and the 7.5 were the only ones that fit. The cover is an 8.8 cover and I measured the ring size and it is 8.8 inches. Has any one else experienced this?

 

[RonD]

Ranger 7.5" and 8.8" have same size tubes and axles, so yes that would be the case for the seals

Explorer 8.8" were larger tubes and axles so different seals.
2010 and up Rangers got the larger tube 8.8" but axles stayed same size

Good read here: http://www.therangerstation.com/tech_library/Ford-8_8-axle.shtml

 

[4x4junkie]

Like many others before you, you simply ran up against the error that is the chain auto parts store reference computer (and this is by no means the only error that has continued to fester unabated in their systems for decades ).

The 7.5" & Ranger 8.8" (thru '09) do use the same tubes, bearings, seals, end plates, and even axle shafts. They also have the same load capacities (2750lbs).

I often say to people: if you're replacing rear bearings, seals, or shafts on ANY Ranger regardless of engine or year (prior to '10), you always say you have the 7.5" axle. The only exception is if you have a '02 (only) FX4 or any year FX4-Level II Ranger (in which case for all parts except shafts, you say you have a '91-'94 Explorer).
Saying you have that year Explorer also avoids all the headache questions about your front axle when replacing brake or wheel-end parts on a '91-'94 4x4 Ranger too.

2010 and up Rangers got the larger tube 8.8" but axles stayed same size

I think the '10, '11 Ranger axles have the larger bearings & seals like the Ex 8.8, but are still 28 spline at the diff.

I recall there was a thread on this just a few months ago too, I'll see if I can find it...

Yeah here it is:
http://www.therangerstation.com/forums/showthread.php?t=166349

Definitely has bigger bearings (and they are not interchangeable with earlier shafts).

 

[ksack]

The 7.5" & Ranger 8.8" (thru '09) do use the same tubes, bearings, seals, end plates, and even axle shafts. They also have the same load capacities (2750lbs).

So theoretically, if I have a 7.5", I could swap in 8.8 gears and 31 spline shafts and have myself a beefier axle or am I missing something?

 

[adsm08]

So theoretically, if I have a 7.5", I could swap in 8.8 gears and 31 spline shafts and have myself a beefier axle or am I missing something?

The tubes are the same. That's it. The 8.8 gears won't clear your diff housing or bolt to your carrier. The 8.8 carrier bearings wont fit your journals. Oh, and the 31 spline axles don't fit throught the 288 spline axle bearings and the 31 spline bearings wont fit your tubes.

If it was as simple as just swapping gears and shafts someone would have figured it out a long time ago.

 

[4x4junkie]

So theoretically, if I have a 7.5", I could swap in 8.8 gears and 31 spline shafts and have myself a beefier axle or am I missing something?

I probably should've made it clearer in my post: the wheel bearings (in addition to the other items I mentioned) are what are the same on the 7.5" & Ranger 8.8". As was stated, parts inside the diff housing itself will not interchange between the two.

The only way to get 31 spline shafts on a Ranger axle housing is to already have an 8.8" to begin with, then have custom shafts made by a company such as Moser, then install a 31-spline 8.8" differential.

Swapping the whole axle for an Explorer 8.8" is almost always the better easier option. The Ex 8.8 with it's larger wheel bearings actually has a better GAWR, and maintains better parts availability should you ever need parts for it down the road (being able to find shafts at a wrecker for example), so this is the way I usually recommend to get 31 splines on a Ranger regardless of which axle it has to begin with. The Explorer 8.8" requires a bit of welding for it to fit under a Ranger.

http://www.therangerstation.com/tech_library/Explorer8_8.shtml

Welcome to the forum

 

[ksack]

Thanks for getting back on that! I'm more than likely going to go with the explorer 8.8 and chop down the long side to make it the same length as the other. That makes it same width as the stock 7.5 on my 86. Summit sells Moser axles in various lengths for the explorer and you can buy them for individual sides

 

[4x4junkie]

I don't think that's a good idea... The diff is offset like that so that the driveshaft doesn't hit against the fuel tank when the suspension flexes under certain conditions (and even still it sometimes hits on mine).

Unless your truck is lowered and/or you need the tires to tuck inside the fenders, the extra width shouldn't be an issue (and it matches up perfectly if yours is 4WD and you've also done the Dana35 swap).

 

[AllanD]

As 4x4 Junkie states, the diff is offset in the rear for DAMNED GOOD REASONS.


(Driveshaft Vs gas-tank clearance as a start)

Another reason is that due to "legacy design issues" in the Cologne engine family (2.8, 2.9, 4.0 (OHV) & 4.0 (OHC)) the crankshaft is not technically centered in the engine block


This is all based on the fact that the ORIGINAL FORD COLOGNE ENGINE was not a V6,
but was instead an inherently unbalanced 60deg V4 engine, that used a balance-shaft to keep it from shaking the car it was bolted into to pieces... (a 60degV4 will vibrate in all three axis)

So when redesigning it as a V6 the crankshaft was offset, this was eventually taken advantage of after the introduction of the 4.0OHC when once again SOME variants of the engine were equipped with a balance shaft....

But when Designing the Ranger Ford always planned on using the "Cologne" 2.8 V6 so offset the driveshaft in the original chassis, transmission and rear axle designs

This is why the original Ranger Manual trans the "Ranger5" or T-K5 transmission is "canted" towards the drivers side so to angle the shifter towards the driver and the output shaft to the passenger side to prevent rear driveshaft phase vibration issues...

the idea here is that to avoid vibration with simple "Cross-joint" drives-hafts you need to keep the transmission output-shaft and the differential pinion-shaft parallel in two planes.

Offset either vertical or horizontal of more than a few degrees will create vibration that is hard to eliminate...


At this point I'll say that Factory Engineers are a bit smarter than most people will
give them credit for...

AD

 

[pjtoledo]

As 4x4 Junkie states, the diff is offset in the rear for DAMNED GOOD REASONS.


(Driveshaft Vs gas-tank clearance as a start)

Another reason is that due to "legacy design issues" in the Cologne engine family (2.8, 2.9, 4.0 (OHV) & 4.0 (OHC)) the crankshaft is not technically centered in the engine block


This is all based on the fact that the ORIGINAL FORD COLOGNE ENGINE was not a V6,
but was instead an inherently unbalanced 60deg V4 engine, that used a balance-shaft to keep it from shaking the car it was bolted into to pieces... (a 60degV4 will vibrate in all three axis)

So when redesigning it as a V6 the crankshaft was offset, this was eventually taken advantage of after the introduction of the 4.0OHC when once again SOME variants of the engine were equipped with a balance shaft....

But when Designing the Ranger Ford always planned on using the "Cologne" 2.8 V6 so offset the driveshaft in the original chassis, transmission and rear axle designs

This is why the original Ranger Manual trans the "Ranger5" or T-K5 transmission is "canted" towards the drivers side so to angle the shifter towards the driver and the output shaft to the passenger side to prevent rear driveshaft phase vibration issues...

the idea here is that to avoid vibration with simple "Cross-joint" drives-hafts you need to keep the transmission output-shaft and the differential pinion-shaft parallel in two planes.

Offset either vertical or horizontal of more than a few degrees will create vibration that is hard to eliminate...


At this point I'll say that Factory Engineers are a bit smarter than most people will
give them credit for...

AD

it's too bad the bean counters then get in the way

 

[AllanD]

The real problems start when Half-smart shade tree engineers start changing things to "fix them" when they aren't actually broken and create new problems they wouldn't have if they had just kept their meddling hands in their pockets...

Not referring to anyone in this discussion, as there are people asking questions and others providing answers to questions that few know enough of the details to ask in the first place.


Hell most don't know that some SHOC engines have a balance shaft hidden in the oil pan assembly...

 

[pjtoledo]

SHOC ???







its late, time to start the smart-assed attitude

 

[347 Ranger]

One thing that helps when installing a 31 spline Axle in a Ranger that came with 8.8 is the Fox body Mustang and early Ranger uses the same housing ends! Ford sold a 31 spline up date kit for the mustang! The kit came with 31 spline posi track and a set of 31 spline axles with a set of C clip
eliminators! These were a Moser part the ones that fit a ranger housing with 28 spline are PN: 9300. The 31 spline C-Clip eliminator is PN: 9333!
What I would like to know is if there is a C-Clip eliminator kit to fit an Explorer with 31 spline axle?

 

[4x4junkie]

What I would like to know is if there is a C-Clip eliminator kit to fit an Explorer with 31 spline axle?

Someone (Superior Axle, I think?) had a c-clip eliminator available for the Explorer 8.8", however I don't think demand was very strong for it simply because... the stock 31-spline shafts hardly ever break. Last i read they had discontinued it.

If you have a disc-brake axle, the shaft shouldn't walk it's way out of the housing in the unlikely event you do break a shaft (the brake disc will hold it in place).

 

[347 Ranger]

Someone (Superior Axle, I think?) had a c-clip eliminator available for the Explorer 8.8", however I don't think demand was very strong for it simply because... the stock 31-spline shafts hardly ever break. Last i read they had discontinued it.

If you have a disc-brake axle, the shaft shouldn't walk it's way out of the housing in the unlikely event you do break a shaft (the brake disc will hold it in place).

Thanks for the reply my Explorer Housing is a Drum brake 1991 Housing in a 1978 Cobra II Drag car! that is why It is supposed to have a C- Clip Eliminator!