No 4.30 gears for the front differential?

[gw33gp]

While searching for 4.56 gears for my Ranger, I discovered I can get 4.30 gears for the rear but I could not find them for the front differential. Is there something about the front differential that will not accommodate the 4.30 ratio?

It looked like the 4.30 gears would have been a better ratio for me.

 

[4x4junkie]

I think manufacturers simply tend to go for what is (or what they think will be) most popular. The HP D35 has a wider set of ratios available, however 4.30 isn't among them either.

I think 4.30 sales would likely be a small fraction of what 4.56, 4.88 and even 5.13 sales are, partly because 4.30 is hardly removed from 4.10, which was a common OEM ratio (at least for the LP D35s anyway).

 

[Captain Ledd]

The 8.8 has a ridiculous amount of ratio options. One of the largest for an automotive axle.

 

[adsm08]

Yeah, 4.30 gears are kind of an odd ratio. They are so close to 4.10 and 4.56 that it would be hard for a driver to notice the difference from either.

 

[gw33gp]

I agree with all that was said but the final drive ratio going from 31" tires with 4.10 gear to 33" tires with 4.30 gears is much closer than with 4.56 gears. The 4.56 gears are better for off-road with the taller tires but I still use 31" tires for daily driving and towing. The 4.30 gears would have been a nice compromise.

Oh well, the 4.56 gears should still work for me. They will arrive today so once I get them in I will know for sure.

My greatest concern is when I am towing. With the 4.1 gears I tow in 4th at 72 and that is about 3200 rpm. With 4.56 gears it will be running about 3600 rpm at 72. That is a little higher than I like to run long distances. If I go into 5th gear it will drop the rpm down to about 2900 rpm which is OK. However, I don't like to use 5th gear when I am towing, but maybe the 4.56 gears will make it easier on the transmission and be OK.

 

[4x4junkie]

If you're on flat road, I suspect you'd be fine in 5th (I've always done it like that with mine). Any slight incline I'd certainly say put it in 4th for though.

Yes, deeper axle gears do take a good bit of load off the trans.

 

[gw33gp]

4x4junkie, that is good to know. I tried towing on a flat section of Interstate with my 89 Ranger 2.9L with the Mitsubishi transmission in 5th. After barely 30 minutes, it over heated the transmission so much that I could barely shift the gears when I pulled into a rest stop.

After letting it cool down for 30 minutes or so, it went back to shifting normally. I never used 5th again in that Ranger while towing. I carried that policy to my 02. Glad to hear someone has a good experience with towing in 5th. I hope that is with the Mazda transmission.

Is there any way to put a cooler on a manual?

 

[4x4junkie]

The Mitsubishi has been known to keel under a sustained load like that. The M5OD with it's tapered-roller bearings and less-aggressive gear tooth angle handles such load a lot better.

As for a cooler, I don't see any practical way of adding one without drilling into the side of the case. Maybe if you got creative you could epoxy a bunch of aluminum fins to the sides of it IMO, I think if you keep on top of changing the fluid every 30K or so that you'll be OK. Again, just remember to downshift if you start up a gentle grade.