Breaking axles

[RR|Suki]

People who are breaking 28 spline axles, are you breaking them at the spline or somewhere in the middle? I'm thinking about what is really breaking instead of going to 31 spline just cuz everyone else does. Also my next question is are the 31s thicker? or is it the same diameter axle with more splines?

[Vortech347]

Same diameter just more splines.

Also aftermarket ones are usually hardnened a little further making them stronger. But when they do break they shatter like glass.

[RR|Suki]

So is anyone stripping out the splines?

[ImpalaSlayer]

what else do you have in mind suki?

[ctrlraven]

Good question to ask.

[Bradley G]

The only instance I recall of someone breaking axles on their Marauder was MartyO .
I don't recall the splines being the area where it broke.
Hey Big Guy! tell us where your axles sheared off?

So is anyone stripping out the splines?

[ImpalaSlayer]

there have been plenty that have broke them. i saw Nate break his, was pretty damn loud too.

[RR|Suki]

Well I was looking into just getting better 28 spline axles and putting new clutches and spring into the current LSD. If the splines aren't stripping I wonder if it's the 31spline that's better, or just better quality axles would do the trick. :confused:

[ImpalaSlayer]

Well I was looking into just getting better 28 spline axles and putting new clutches and spring into the current LSD. If the splines aren't stripping I wonder if it's the 31spline that's better, or just better quality axles would do the trick. :confused:

good question! letme know what you find.

[Vortech347]

With these cars being auto's is very unlikely you'll break them.

The only axle I've ever seen personally was my buddy's mach. 6800rpm clutch dump with 12" wide slicks. He didn't move an inch. With our cars we can "preload" the drivetrain getting taking the slack that "slams" when you take off. Even then they didnt' break at the splines, it broke in the middle. Like I said, shattered like glass.

I run 28' spline axles in my stang that consistantly does 1.6 60's and has made about 100 passes on them like this.

You can get 31 spline ones from moser but you'll need to change your dif out.

[RR|Suki]

With these cars being auto's is very unlikely you'll break them.

The only axle I've ever seen personally was my buddy's mach. 6800rpm clutch dump with 12" wide slicks. He didn't move an inch. With our cars we can "preload" the drivetrain getting taking the slack that "slams" when you take off. Even then they didnt' break at the splines, it broke in the middle. Like I said, shattered like glass.

I run 28' spline axles in my stang that consistantly does 1.6 60's and has made about 100 passes on them like this.

You can get 31 spline ones from moser but you'll need to change your dif out.

Already know all that, but there have been a number of cars on here that have broken axles, a couple make less power than I do, so I wanna know what is really breaking so I can make a "just in-case" plan. Now that I have the slicks and I've gone and done a couple 1/8 runs on em I'll prob be leaving at 3K when I go to a track with timing equipment.

[Bradley G]

Then say good by to that old 60' time! :bows:
Already know all that, but there have been a number of cars on here that have broken axles, a couple make less power than I do, so I wanna know what is really breaking so I can make a "just in-case" plan. Now that I have the slicks and I've gone and done a couple 1/8 runs on em I'll prob be leaving at 3K when I go to a track with timing equipment.

[RR|Suki]

Then say good by to that old 60' time! :bows:

Indeed, the time in my sig is leaving off idle with only 1/2 throttle until 2nd gear, street tires just dont cut it. I'm addicted to these slicks now after playing with them yesterday.

[jdando]

The only instance I recall of someone breaking axles on their Marauder was MartyO .
I don't recall the splines being the area where it broke.
Hey Big Guy! tell us where your axles sheared off?

Bradley you must be getting old, and forgetting stuff.

Mike C (Mrogerc) tore up an axle here in MN.

http://www.mercurymarauder.net/forums/showthread.php?t=19587&highlight=axle&page=2

There are links to pictures there also.

[Joe Walsh]

Nate (NATEHAWK) snapped an axle (28 spline OEM IIRC)

[stangracr]

I have broken 3 28 spline axles in my Mustang with a stroked 5.0 Finally put 31 spline axles in with no problems since. The reason 28 spline axles break is where the splines are gets smaller unlike the 31 spline axles that are the same size end to end. They always break at the splines. So the answer is. 31 spline axles are bigger at the splines then 28 spline axles are.



ed

[DOOM]

I'm doing a Detroit tru trac next month so I have no choice but to go with 31 spline because they don't make it for the 28 spline.

Also Nate has an early 03 car which I believe had the soft axle issue some of the early builds had (mine is a 04). Maybe some of the people who have broke their axles will chime in.
I'm curious to see if they were mostly the early 03's

[ginson3]

I am about three weeks into the True-Trac, Moser 31's, & motive 3:73's. The 31's are quite a bit bigger than the 28's. If I remember correctly Dennis Reinhart has a side by side photo of them on his website.

[CRUZTAKER]

OK...bear with me here as I am not a gear head....

Do you have to replace the rear gear and lsd to accomodate 31's?
Or is is just an axle upgrade?

I have had thoughts of doing this sooner than later (of being towed home) in the next mod mood.

[ImpalaSlayer]

OK...bear with me here as I am not a gear head....

Do you have to replace the rear gear and lsd to accomodate 31's?
Or is is just an axle upgrade?

I have had thoughts of doing this sooner than later (of being towed home) in the next mod mood.

yup, the whole thing. ring and pinion are the same though

[ginson3]

I don't think you have to replace the carrier, but you would have to modify with side gears from a 31 spline carrier like the '03-04 Cobra (I think). Seems like i saw parts
on ebay to do that on Ebay for around a hundred bucks, or you can buy a new Ford Racing carrier ready to go for about 3 hundred. You might want to consider "national drivetrain" they were a tremendous amount of help, provided the best service I have had in a very long time, and had the best prices to boot. Good luck with which ever way you go.

[ntd]

I always wondered if you could use 31 spline side gears from the newer ford CVPI in our carriers? Would save you the labor to adjust gear backlash.

[ginson3]

I was pretty sure they made the True-Trac for the 8.8. The 31 spline is slightly cheaper though. I paid $410.00 for the 31 spline
http://nationaldrivetrain.com/shopsite_sc/store/html/media/TRUE_photo4SMALL.jpg DETROIT TRUETRAC FORD 8.8 - 28 SPL ALL RATIOS
$445.95
912A562
DETROIT TRUETRAC FORD 8.8 - 28 SPL ALL RATIOS

[Bradley G]

You are spot on Jeremy!
Thanks for the refresher!
At least I did not post in that thread!
Bradley you must be getting old, and forgetting stuff.

Mike C (Mrogerc) tore up an axle here in MN.

http://www.mercurymarauder.net/forums/showthread.php?t=19587&highlight=axle&page=2

There are links to pictures there also.

[imorb1994]

When I broke an axle, it was in between the(carrier) bearing and the splines. It exploded and took the carrier with it. Mine were OEM 28 spline. Don't quote me on this but I do believe the inlet(on the sides) of 31 spline carriers, is slighty larger.

[stangracr]

gotta change the carrier. 31 spline side gears wont work in a 28 spline carrier.



ed

[RR|Suki]

so it's looking like they are breaking where the axle narrows towards the end, good info indeed, keep it coming.

[RacerX]

I have two 28 spline axles from Mike's KB-MM. They're in great shape and he had a lot of ponies going to the rear end. The 4.10's, pinion, carrier and spider gears look mint. You don't need a new carrier, you can get new side gears for inside the carrier that are for 31 spline axles. I don't remember if you have to replace the frictions and steels.

[Blown3.8]

On our automatic cars they usually break from wheel hopping stiff sidewall tires, ie. drag radials. Less chance of breaking an axle with bias ply slicks.

The 31 spline axle is same diameter all the way from the splines to the hub. 28's neck down at the splines like mentioned previously. And thats where they normally break.

[babbage]

Ah and then also you can get new aftermarket 28 spline axles from Dorman. They use rolled splines instead of cut splines - the splines on these axles are 35% stronger than cut splines.

Dorman Part number: 630-214 (https://www.dormanproducts.com/cgi-bin/vm91corp30r/item-dtl.w?sid=kCdrjkctTYEadbfU0117 33921031749809&item=630-214&icrid=0x001812e9&clt=hwrap1&vsrch_str=&vsrch_brand=&vsrch_cat=&st_amount=&end_amount=&start=&vfrom=&prev=&vnext=&category_list=:0:0:0)

[RacerX]

Hmmmm... I wonder if the ones that broke axles had stiffer control arms or not??? That would prevent wheel hop wouldn't it?

[MCAT]

Fwiw a 28 spline axle has a bigger spline, the 31 spline axle is a smaller more compact design with more surface engagment, I would suspect
the 28 spline axle's are breaking at the Hob (tool used for cutting spline's & gears) sweepout, when you go with a finner pitched spline the root
of the spline is not as deep making the transition much smaller,
allowing it to take more stress, a lot of after market axles are cut
on a mill one spline at a time & depending on the mill Dia. &
if you have the machine sweep out you can make a more gradual
transition @ the end of the cut also helping to reduce the week spot.

to sum it up the more spline's the less deep you have to cut in to the shaft.:D

[Stranger in the Black Sedan]

^great explanation!!!! thanks

[babbage]

Fwiw a 28 spline axle has a bigger spline, the 31 spline axle is a smaller more compact design with more surface engagment, I would suspect
the 28 spline axle's are breaking at the Hob (tool used for cutting spline's & gears) sweepout, when you go with a finner pitched spline the root
of the spline is not as deep making the transition much smaller,
allowing it to take more stress, a lot of after market axles are cut
on a mill one spline at a time & depending on the mill Dia. &
if you have the machine sweep out you can make a more gradual
transition @ the end of the cut also helping to reduce the week spot.

to sum it up the more spline's the less deep you have to cut in to the shaft.:D

.... unless you get Dorman 28 spline Axles - they are folded splines (35% stronger) not cut.

[imorb1994]

Hmmmm... I wonder if the ones that broke axles had stiffer control arms or not??? That would prevent wheel hop wouldn't it?
I have the metco's, and had wheel hop when my axle broke.

[mpearce]

RR...believe it or not, this thread with comparison pictures was instrumental in my choice.

http://www.mercurymarauder.net/forums/showthread.php?t=16305&highlight=spline


I know you are one of those guys that likes to do his own thing...and I respect that...but IMO...it's more fun to be out there racing, than at home stewing over how you can safely run 28 splines at your power level.

The stock axles were lasting way back when...when 500HP Marauders weren't commonplace. Until people started widening the wheels and putting on drag radials...or ET streets like CRUZTAKER. As soon as the sticky's went in the rear...bye bye axles. Lidio broke his, as well as Dave. IIRC...they both sheared in the middle of the axle...in a twisting motion. There's a picture somewhere...but I couldn't find it. Trust me man...your MM is high HP...and when you do hook that thing at the track...you'll break the stock set up eventually.

I upgraded to the 31 spline axle and posi set up an entire year before my blower went on. I didn't have any problems with my stock LSD, I just knew I was headed for high HP when the blower went on...so I didn't mess around. Also, I believe the Moser 31's axles are forged maybe? I'm not exactly sure though.

Good luck!

-Mat

[MCAT]

.... unless you get Dorman 28 spline Axles - they are folded splines (35% stronger) not cut.

Oh yes "spline rolling" is stronger, kinda forgot about that, we don't
do that in house at the shop, but do send some jobs out for rolling.

although the finish is a bit crude, find of like cold forging.

[MCAT]

[quote=mpearce;812878]RR...believe it or not, this thread with comparison pictures was instrumental in my choice.

http://www.mercurymarauder.net/forums/showthread.php?t=16305&highlight=spline

now i have not seen any our stock mm axles in person, but looking
at these pictures, the stock 28's are rolled on a much small (necked down dia.) & the 31's are cut (with a mill) right on the dia. that runs the length of the axle.
(there may be a gradual taper in the axles from end to end)

[Glenn]

Ah and then also you can get new aftermarket 28 spline axles from Dorman. They use rolled splines instead of cut splines - the splines on these axles are 35% stronger than cut splines.

Dorman Part number: 630-214 (https://www.dormanproducts.com/cgi-bin/vm91corp30r/item-dtl.w?sid=kCdrjkctTYEadbfU0117 33921031749809&item=630-214&icrid=0x001812e9&clt=hwrap1&vsrch_str=&vsrch_brand=&vsrch_cat=&st_amount=&end_amount=&start=&vfrom=&prev=&vnext=&category_list=:0:0:0)

How can one order from Dorman without being a distributor or retailer. What is the cost of the axles?

Glenn :burnout:

[Stranger in the Black Sedan]

aren't factory splines already rolled instead of cut? Dorman stuff can be ordered through any auto parts store like Advance or Autozone. Any of the dorman stuff I have ever used was offshore crap that was a fraction of the cost of OE. The "Better than nothing" type quality stuff. I think the dorman axles are like a hundred bucks each? Not clear on how that is an upgrade from us made OEM axles

[RR|Suki]

RR...believe it or not, this thread with comparison pictures was instrumental in my choice.

http://www.mercurymarauder.net/forums/showthread.php?t=16305&highlight=spline


I know you are one of those guys that likes to do his own thing...and I respect that...but IMO...it's more fun to be out there racing, than at home stewing over how you can safely run 28 splines at your power level.

The stock axles were lasting way back when...when 500HP Marauders weren't commonplace. Until people started widening the wheels and putting on drag radials...or ET streets like CRUZTAKER. As soon as the sticky's went in the rear...bye bye axles. Lidio broke his, as well as Dave. IIRC...they both sheared in the middle of the axle...in a twisting motion. There's a picture somewhere...but I couldn't find it. Trust me man...your MM is high HP...and when you do hook that thing at the track...you'll break the stock set up eventually.

I upgraded to the 31 spline axle and posi set up an entire year before my blower went on. I didn't have any problems with my stock LSD, I just knew I was headed for high HP when the blower went on...so I didn't mess around. Also, I believe the Moser 31's axles are forged maybe? I'm not exactly sure though.

Good luck!

-Mat

that's why I asked, if they are breaking where the axles narrow then I'm not going to even bother looking into new 28s. I'll try not to snap the stockers this year I guess, so I can redo the rear in the spring :lol:

[mpearce]

that's why I asked, if they are breaking where the axles narrow then I'm not going to even bother looking into new 28s. I'll try not to snap the stockers this year I guess, so I can redo the rear in the spring :lol:

Found some pix in the gallery....


http://www.mercurymarauder.net/gallery/data/502/medium/IMG_1735.JPG


http://www.mercurymarauder.net/gallery/data/502/medium/IMG_1737.JPG

[NATEHAWK]

Just upgrade yours man..I was running MT ET Drag Radials and on my take off out the hole when my axle snapped I hooked real well then BOOM. Now I have a Detroit Truetrac with FORD CVPI 31 spline axles. And you can use the same gears. Here is a video of my run when I snapped for ur viewing pleasure

http://www.youtube.com/watch?v=_nQvoNDRIvQ

[JohnE]

I replaced a factory axle shaft with a NAPA made in India on the Grand Marquis a while back. It lasted about 9 months before the wheel bearing wore into the shaft enough to cause the seal to leak. Be careful of the quality of aftermarket. Wound up putting a new OEM axle in.


I plan to install 31 spline Moser in my Marauder when I upgrade the engine.


John

[bob6364]

Pictures of a stock Marauder axle I snap off while launching....no wheel hop,no control arms,not even 4:10's back then,....only a cold air kit and a tune....266rwhp...
Didn't beak on this run,obviously http://s159.photobucket.com/albums/t153/bob6364/Epping/?action=view&current=9-18-2006-26.flv
http://i159.photobucket.com/albums/t153/bob6364/Saleen%20parts/saleen004.jpg
http://i159.photobucket.com/albums/t153/bob6364/Saleen%20parts/saleen003.jpg
http://i159.photobucket.com/albums/t153/bob6364/Saleen%20parts/saleen002.jpg
http://i159.photobucket.com/albums/t153/bob6364/Saleen%20parts/saleen001.jpg

[Bluerauder]

On our automatic cars they usually break from wheel hopping stiff sidewall tires, ie. drag radials. Less chance of breaking an axle with bias ply slicks.

The 31 spline axle is same diameter all the way from the splines to the hub. 28's neck down at the splines like mentioned previously. And thats where they normally break.


Found some pix in the gallery....


http://www.mercurymarauder.net/gallery/data/502/medium/IMG_1735.JPG


http://www.mercurymarauder.net/gallery/data/502/medium/IMG_1737.JPG

With Matt's pix and Chris' explanation, the axle issue with the 28's seems pretty clear to me. Going with the 31's seems to be a no brainer.

[babbage]

I have broken 3 28 spline axles in my Mustang with a stroked 5.0 Finally put 31 spline axles in with no problems since. The reason 28 spline axles break is where the splines are gets smaller unlike the 31 spline axles that are the same size end to end. They always break at the splines. So the answer is. 31 spline axles are bigger at the splines then 28 spline axles are.

ed

I'm sure I've said this more than once but here goes again. Inexpensive and easy to install Dorman aftermarket 28 spline axles are *rolled spline* instead of cut spline. Difference: They are said to be 30% stronger than OEM. I may get new dormans in the future, I wanted to use my FORD ESP warranty when mine go bad.

Ooops I already posted this. Duh Sorry Guys.

Glenn: You can buy them at Summit Racing. http://www.summitracing.com/parts/RNB-630-214 - Everyone sells them Just google "Dorman 630-214"
$121 Bux Each. Not a bad deal really.

[ntd]

Just upgrade yours man..I was running MT ET Drag Radials and on my take off out the hole when my axle snapped I hooked real well then BOOM. Now I have a Detroit Truetrac with FORD CVPI 31 spline axles. And you can use the same gears. Here is a video of my run when I snapped for ur viewing pleasure

http://www.youtube.com/watch?v=_nQvoNDRIvQ

natehawk how long have you been running the 31 spline cvpi axles?

[GreekGod]

Ford went to the 31 spline axles on all Panther chassis cars in 2005. The 31 spline gears for the 28 spline differential are no longer available.

Rock Auto sells 31 splines axles, made in USA, and they come with the ABS rings and studs installed.

Moser is a good alternative source, but you need to add ABS rings and studs to an order. Rolled threads have superior strength to cut threads.

==================

[ImpalaSlayer]

so any 31 spline axle from a panter will work right? looks like rock auto sells them for 108 a piece.

[GreekGod]

so any 31 spline axle from a panter will work right? looks like rock auto sells them for 108 a piece.

I used Rock Auto's 31 spline axles in my 2000 Crown Vic (unbeatable prices). The 2003-2009 axles should all be the same length (2005< are all 31 spline). Pre 2003 are a different length, and some have ABS, while some don't.

If you "play" with the years & options on Rock Auto's website, you can figure out the year & model (Crown Vic, Gran Marquis, Town Car, Town Car Limo) interchange/part numbers.

============================== ========

[ImpalaSlayer]

cool. i just put in 05 cv and it comes up as 31 splines so i should be good to go there. now i just gotta figgure out a center section :hmmm:

[RR|Suki]

cool. i just put in 05 cv and it comes up as 31 splines so i should be good to go there. now i just gotta figgure out a center section :hmmm:

there are cheap ford racing ones with the carbon clutches on ebay new

[GreekGod]

While the contact patch and "stick" of tires is a major factor in axle breakage, the diameter (of rear tires) is also. The torque loading increases as the diameter (effective radius) of the tire increases. Similar to the load on brakes, when using larger O.D. wheels.

========

[merc]

While the contact patch and "stick" of tires is a major factor in axle breakage, the diameter (of rear tires) is also. The torque loading increases as the diameter (effective radius) of the tire increases. Similar to the load on brakes, when using larger O.D. wheels.

========


Fact. No Marauder axles to my knowledge have been broken on bais ply slicks, DOT or non DOT. It's all about the side walls and energy transfer. You can put the largest tire in the world under your rear fenders. If that tires spins on the line everything is good, but if it sticks and grips it will transfer that energy to the axles. Take a closer look a the axle pictures in this thread. You will see the the axle twist that I am talking about.

[NATEHAWK]

natehawk how long have you been running the 31 spline cvpi axles?

Since around march -april this year. Alot of the guys that race on here use 31 spline axles with no problem.


Fact. No Marauder axles to my knowledge have been broken on bais ply slicks, DOT or non DOT. It's all about the side walls and energy transfer. You can put the largest tire in the world under your rear fenders. If that tires spins on the line everything is good, but if it sticks and grips it will transfer that energy to the axles. Take a closer look a the axle pictures in this thread. You will see the the axle twist that I am talking about.

FACT your axles will break if you got a good tire that sticks but like merc said does not have a wrinkle wall to allow for a lil play to take some stress off the axle. So me being the guy I am wouldnt make the same dumb move twice I brought a set of MT ET Streets DOT Slicks and now im ready to play :burnout:

[ImpalaSlayer]

Zack saw this thread and hooked me up with a set of 31 cv axles. :woohoo:

[GreekGod]

Fact. No Marauder axles to my knowledge have been broken on bais ply slicks, DOT or non DOT. It's all about the side walls and energy transfer. You can put the largest tire in the world under your rear fenders. If that tires spins on the line everything is good, but if it sticks and grips it will transfer that energy to the axles. Take a closer look a the axle pictures in this thread. You will see the the axle twist that I am talking about. 28 spline axles do not belong on any performance vehicle, let alone a #4,000 SOHC Crown Vic or a (DOHC) Marauder. That is why Ford changed to 31 splines in 2005 (better late than never). The economy of scale make it stupid to inventory 2 different sizes axle shafts & differentials (it seems it took Ford 26 years to realize).

Many Mustang "racers" keep their 28 spline OEM shafts (even with only 4 lug wheels), do wheelies, and run much quicker than our MM's. Just because you can do something, doesn't mean you should.

This was done with my (~#4,000?) 2WD 1968 F100, with a 240 cu in inline 6 cylinder (~110hp), 3 speed manual transmission, 3:50 rear gears (Detroit Locker), and (very hard) N78-15 bias ply tires. The large od of the stiff sidewall contributed to the twist & break:

http://www.mercurymarauder.net/forums/../gallery/data/500/medium/Axle_Shaft_Stub_003.jpg (javascript:;)

[NATEHAWK]

Zack saw this thread and hooked me up with a set of 31 cv axles. :woohoo:

Zack SAW :lol:

[DOOM]

Ford cvpi ftw!!! :banana2:

[Mr. Man]

I've been following this thread and have a question. Forgive me if it seems silly but if I don't ask I won't learn. 31 spline axles are stronger than 28s, got that. Roll formed are stronger than mill cut,got that. Now for the ? If I replace the 28's with 31's will I also have to replace my... say 4:10 gears? I'm a bit confused as to what else needs replacing. If and when I have this done I would like to have all the necessary parts to finish the job in one shot. Thank you in advance for taking the time to answer my question. If there is anything else I should take into consideration please enlighten me.

[RR|Suki]

You need an LSD, the ring and pinion will fit on the new LSD

[GreekGod]

I've been following this thread and have a question. Forgive me if it seems silly but if I don't ask I won't learn. 31 spline axles are stronger than 28s, got that. Roll formed are stronger than mill cut,got that. Now for the ? If I replace the 28's with 31's will I also have to replace my... say 4:10 gears? I'm a bit confused as to what else needs replacing. If and when I have this done I would like to have all the necessary parts to finish the job in one shot. Thank you in advance for taking the time to answer my question. If there is anything else I should take into consideration please enlighten me.

The Ford 8.8" rear axle:

The axle shafts slip into the side gears in your differential. Since 31 spline axles have a larger O.D. than 28's, you need to replace the (28 spline) differential side gears with 31's. 31 spline side gears are not available for the OEM differential in our MM's, ergo you need a different differential.

Ford offers a 2 pinion Limited Slip Differential (LSD), with either standard friction plates, or carbon fiber friction plates. A 2 pinion "open" diff is also available. Ford Racing has a few other options, as well as the aftermarket. The Detroit Locker is considered the strongest.

The 8.8" differential can accommodate any ring & pinion gears from 2.87 (?) to 4.10, without any problems. The 4.30< require some adaption.

When modifying a rear axle, it is wise to install new bearings, pinion seal, and use a solid pinion spacer rather than the collapsible OEM spacer.

=================