28 or 31 Spline

[marine_2003]

Which Axles should I go to? 28 ir 31 Spline?

Thanks

 

[Carney Woods]

If it was me and this is what I did. It's pretty well the same price to upgrade to 31 splines if your changing your differential anyway. I got an explorer diff (31 splines) with 3.73 axles off ebay for 120.00. all I need is the axles so for a little more money there will be no worries in the rearend.............

 

[Realmongo]

Depends on what your differential is splined for.

 

[marine_2003]

Im taking the rearend out of the car, and replacing everything, axles, posi, and gears. So I was wondering what spline to go with.

 

[Sicarius428]

31s definately then.
Kevin

 

[tjm73]

31s definately then.
Kevin

Yeah what this guy said.

 

[powertrax91]

Yeah what this guy said.

 

[Lyncher]

y wouldnt you go with 31s?

 

[CBZGT50]

I called randy's ring and pinion to upgrade my car to 31 spline with a locker during my change to 3.73's. Here is the breakout:

Eason posi: $399.00
Two 31 spl axels $121 each
axle seals and bearings $15.20 each side
Used gears and setup kit (everything) $125.00
Setup $200.00
$996.40

I already have the gears and set up kit. So I am going to be about $850 into mine with new parts and new oil.

 

[SVT32VDOHC]

I went with 31 spline Mosers..and I had DTS build an Explorer 31 spling carrier..it was much cheaper. People tell me now the diff is my weak point, but really....if it breaks I can fix it 3 times and it will still be cheaper than buying any other A.M. diff once. I have been hard on the car with sticky tires and it has been find..many burnouts too.!!! 31s arethe way to go.

 

[TrophyHead]

y wouldnt you go with 31s?

"Sometimes" upgraded 28 spline axels are all you need. I forget how much Moser 28 splines can handle but way more than stockers. Also they weigh a little less than 31's. And on rotating parts less weight is better. Hardcore road racers would consider the less weight. But I agree go with the 31's.

 

[dbdragracing]

I know the traction lock has to be changed when going to 31-spline, but can you use the same gears you are using with the 28-spline? Thanks.

 

[Lyncher]

"Sometimes" upgraded 28 spline axels are all you need. I forget how much Moser 28 splines can handle but way more than stockers. Also they weigh a little less than 31's. And on rotating parts less weight is better. Hardcore road racers would consider the less weight. But I agree go with the 31's.

yeah but the weight difference can really be a noticable amount performance wise...can it? I would just think that the price isnt much diffrent and the added strength is always welcome but thats just how i see it?

 

[TrophyHead]

yeah but the weight difference can really be a noticable amount performance wise...can it? I would just think that the price isnt much diffrent and the added strength is always welcome but thats just how i see it?

http://www.moserengineering.com/moser_interior/axletech.htm

I contacted Moser with a few questions. I'll re-post when they get back to me.

Anybody remember what the rule of thumb is when you lose one pound of rotational mass. How much HP do you gain? I forget.

 

[TrophyHead]

A 28 spline axel is rated at 5,000 lbs per axel. They didnt give me a weight and it's probably not much. So with 400 lbs of TQ, 3.35 first, and 4.10's your still well in check for 28 splines.

They said slicks=31 and up.

 

[blackstangt]

not really, i bent my 28 with less than 400 ft lbs and wide gears (2.95)x(3.08) 1st. I do have like 140k on them though, overhaul on the 8.8 this winter.

 

[fiveohGT]

31's deff.

 

[$uperstang]

31

 

[RustyFox]

not really, i bent my 28 with less than 400 ft lbs and wide gears (2.95)x(3.08) 1st. I do have like 140k on them though, overhaul on the 8.8 this winter.

I'm assuming they were stock 28's.

Has anyone heard of anybody breaking aftermarket 28's with less than 600 hp?