8.8 or 7.5?

[tandangerranger]

Problem was you went to Autozone

I agree, I can't count the number of trips I make back and forth from autozone because they give me the wrong parts. So I will just say my problem is autozone.

 

[Gotta_gofast]

I went there for a diff cover gasket for my 8.8 and they ended up giving me a 7.5". So this last time I asked for an 8.8" differential cover gasket and the kid couldn't find it without looking up a vehicle! So I ended up telling the parts kit it was for an explorer to eliminate any mix ups as the explorer only came with the 8.8.

I try to purchase most of my parts online where I can choose the exact part number. But autozone is close so I cross my fingers and open each box to inspect each part before I drive away now when I go to autozone.

 

[kryptonitecb]

The LAST time I went to autozone was after making three trips for a bearing/seal combo for a vehicle I no longer have. Finally I had to take the part with me covered in grease and gunk, made the kid behind the counter do a part number reference and give me the correct part. I rarely have this problem at O'Reilly's or NAPA, still for bearings and such, I bring the part with me so I can physically compare it before going home to find its the wrong one.

If you have the time I would try to use rockauto.com just beware that if you order the wrong part from them you have to pay to return it.

 

[Tonka]

I'm still wondering what my Ranger was doing with an 8.8 rear end on it, when the door tag calls for a 7.5. It was the same ratio as the door tag, just the larger axle. It even had an adapter U-joint to fit the smaller size drive shaft.

Oh well. Right now it's got a 7.5 with the same 3.45 ratio called for on the door tag, and the speedometer matches the GPS so I'm happy.

 

[kryptonitecb]

The 8.8 is a bit stronger than the 7.5 if you are using it for a toy. If you only plan on staying on the road and not putting an 8-cyl in then no reason you won't be happy with the 7.5.

 

[dla]

The 8.8 is a bit stronger than the 7.5 if you are using it for a toy. If you only plan on staying on the road and not putting an 8-cyl in then no reason you won't be happy with the 7.5.

Well you will notice the weakness of the 7.5 when doing things that little trucks get used for - like hauling a 1000lbs of something. Axle bearings wear out pretty fast. I replaced both of mine at 60K miles. A 5lb slide hammer, bearing puller and little know-how makes it OK, but an 8.8 rear end is a much better solution. The 8.8 is what Ford should've used in the first place.

 

[pillen140]

The bearing for a 7.5 and 8.8 are the same, the difference is the carrier itself, its something like 20% stronger according to ford.

 

[tandangerranger]

Did fx4 rangers have 31 spline axle?

 

[Gotta_gofast]

Only level 2 FX4 axles with the torsen differential used the 31 spline 8.8. The 28 spline 8.8 is more like a hybrid of 8.8 differential and 7.5" axle. The load carrying capacity of the 7.5 is the same as the 8.8 axle so 1000lbs of weight won't expose the 7.5" axle's "weakness". I believe the torque capacity is the only thing ford rates the 8.8 higher than the 7.5 axle. This is why it's used behind engines with more power.

With factory size tires, the 7.5" axle will handle the towing/hauling needs of any 2.3, 2.9, or 3.0 engine (as long as you stick to your owner's manual's recommendation).

 

[dla]

The load carrying capacity of the 7.5 is the same as the 8.8 axle so 1000lbs of weight won't expose the 7.5" axle's "weakness".

I'm not sure which 8.8 you are comparing a 7.5 to. If 28spline 8.8 to 28spline 7.5, then you are probably correct about the load rating. If 28spline anything to 8.8 31spline then you are totally wrong. The ford 8.8 31spline is a much, much stronger axle.

And yes, hauling around a 1000lbs will munch the axle bearings fast on a 7.5. Most folks don't check them until they start leaking, which is way too late.

 

[Gotta_gofast]

I'm not sure which 8.8 you are comparing a 7.5 to. If 28spline 8.8 to 28spline 7.5, then you are probably correct about the load rating. If 28spline anything to 8.8 31spline then you are totally wrong. The ford 8.8 31spline is a much, much stronger axle.

And yes, hauling around a 1000lbs will munch the axle bearings fast on a 7.5. Most folks don't check them until they start leaking, which is way too late.

Ranger 8.8 vs Ranger 7.5. The 31 spline axle is 30% stronger as far as weight carrying capacity than the 8.8 28 spline.

And if you think 1000lbs chews up a 7.5" axle bearing, then you surely mean that 1000lbs chews up 28 spline 8.8 axle bearings since the bearings are identical between the two (as is axle shaft diameter).

 

[dla]

Ranger 8.8 vs Ranger 7.5. The 31 spline axle is 30% stronger as far as weight carrying capacity than the 8.8 28 spline.

And if you think 1000lbs chews up a 7.5" axle bearing, then you surely mean that 1000lbs chews up 28 spline 8.8 axle bearings since the bearings are identical between the two (as is axle shaft diameter).

Duh. That's what I said.

 

[Gotta_gofast]

Then we are in agreement.

 

[brinker88]

^Love this shit lol