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Unread 10-02-2008, 05:00 PM   #16
Paulio91184
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Originally Posted by Paulio91184
.8.8 is like 120% stronger than the D35. not a tested and published statistic.
Maybe not numbers wise but put 4.10 gears and 33's on a D35 and its a recipe for disaster

plus the 8.8 tubes are much bigger and thicker..
They are larger in dia, BUT thinner walled. There is rumor of a .250 wall housing. But of the 25 or so samples in a pull a part here all were .187. These were under everything from Mustangs, Explorers, F150 and, Crown Vic's...........That i did not know, guess i can't believe everything i hear


just a much more robust axle and you get free disc brakes too!! not on all 8.8's............he said 98 and up so that is what i was refering to

just make sure to weld the center section to the tubes if you do go this route...If you need to weld the casting to the tubes, how can it be a more robust axle?...............You don't really have to weld it but welding the tubes vs building an entire axle like the D35 up just isn't worth it in my opinion


I can weld so for me the 8.8 is just a better option

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Unread 10-02-2008, 05:09 PM   #17
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points taken
but in the end you end up with an unlocked axle for the money of a locked S35
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Unread 10-02-2008, 05:13 PM   #18
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Ive run 9+ rated trails in colorado with a super 35 with 456 gears 35" tires and have never had a problem. And the use of the saying " you cant polish a turd" is a joke. The super 35 is a good way to go if you dont plan on tires over 35".
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Unread 10-02-2008, 09:10 PM   #19
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Quote:
Originally Posted by Rowdy115 View Post
Thanks for this, but I have seen this one before. Is there a comparison chart out there that compares the "Super" Dana 35 shafts to the others listed above? That is what I can't seem to find using Google.com What is the COT and MOT numbers for a 30 spline Super Dana 35 shaft?

Thanks.
I'll bet you won't find published info on a Super35. Don't put money into a D35c, its a crap axle, always has been, always will be. You can put all the money you want into it, and its still a crap axle. The housing and tubes will still be thin, the ring gear will still be small, you'll still be limited by gear ratios, and you'll still see housing flex.

So answer your questions...you can calculate the THEORETICAL strength of any solid bar pretty easily (like and axle). Its a typical undergraduate physics & engineering problem dealing with the moment of inertia: http://en.wikipedia.org/wiki/Moment_of_inertia Go figure out the yeild strength of each alloy of steel, then learn some physics and it will take you about 15 minutes to do your calculations.

But, axle shafts are not the only thing contributing to the strength. You've got a lot more factors like:
1. size of the ring gear
2. tube thickness
3. housing thickness
4. housing flex
5. size of pinion gear
6. size of bearings
7. c-clip vs non-clip
8. semi-float vs full-float
9. alloy of metals involved in all of the above

The short answer is simple:
8.8 > D44 > D35c
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Unread 10-02-2008, 10:02 PM   #20
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have not done an axle swap as of yet and have watching and reading all the posts that i can in hopes to one day swapping my Dana 35 for something different. i can see advantages to the S35 upgrade, D44 and the 8.8, all have there pros and cons in their way. i think it is just up to the owner, his budget, skill level and time. also it makes a difference if the jeep is a DD or strictly a trail rig. all the info was very helpful. thanks for all the info and your opinions i will keep watching this thread just to educate myself on all the different options.
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Unread 10-02-2008, 10:03 PM   #21
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Quote:
Originally Posted by Unlimited04 View Post


Search:
I found this with google in less than 10 seconds:
http://www.jeepforum.com/forum/showp...98&postcount=1
you should post up the whole thread:

http://www.jeepforum.com/forum/showt...98#post5461998
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Unread 10-02-2008, 10:24 PM   #22
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Originally Posted by never monday View Post
answers in red
I will say that you were fair in this post....but when we hear about 8.8's bending tubes it will become an issue. I haven't heard of one to this point....and not all 8.8's were created equal - for example, the ranger 8.8 doesn't even have the same tube diameter....short of cutting up my 8.8, there is no way to find out how thick my tubes are...but again, I have never heard of one of them bending.

as far as "not all 8.8's have disk brakes" - well, the guy who pulls one with drums is a fool...so that point is moot too.


is the differential housing bigger than the D35? yep...I can see how some would take issue with that, but i can't imagine anyone complaining about dana 60's being bigger either....

so again, it comes down to personal choice i think we can both agree.
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Unread 10-02-2008, 11:26 PM   #23
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one of these days i will get back on that ju thread and start working on it again....
it sure would be nice if someone would do a test on superior super 35 shafts, super 88 shafts and maybe some of the other aftermarket shafts available.

that thread can never be 100% correct but it is a hell of a resource for those willing to do something for their jeep and have skills and spare time. not only do i like the 8.8... i also like the super 35. my father has been using one for years. both are great choices.
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Unread 10-03-2008, 04:27 AM   #24
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Quote:
Originally Posted by Greg_Volkman View Post
short of cutting up my 8.8, there is no way to find out how thick my tubes are...
Take a small piece of steel, say an old feeler gauge and cut a .300 slot in it. Then pull the breather fitting off of the axle tube. Now you can insert the shim, hook the axle tube in the notch and measure the gap with feeler gauges. Subtract the sum of the feeler gauges for .300 and you have the wall thickness.

is the differential housing bigger than the D35? yep...I can see how some would take issue with that, but i can't imagine anyone complaining about dana 60's being bigger either....
All this argument is based on running 35's, some times smaller is better
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Unread 10-03-2008, 04:42 AM   #25
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1. size of the ring gear - until they fail it's a moot point
2. tube thickness - 35/44 > 8.8
3. housing thickness - don't know
4. housing flex - no way to measure
5. size of pinion gear 8.8 > 35 > 44
6. size of bearings - Carrier, wheel, pinion which ones?
7. c-clip vs non-clip - moot point all can be non c-clip
8. semi-float vs full-float - all are semi float
9. alloy of metals involved in all of the above - beyond my pay grade

Quote:
The short answer is simple:
8.8 > D44 > D35c
This should read F8.8 = D44 > D35c
but it's a misleading statement. Your comparing the D35c, not a S35.

now, the correct way it should flow is D44 = 8.8 = S35
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Unread 10-03-2008, 08:08 AM   #26
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Quote:
Originally Posted by never monday View Post
Take a small piece of steel, say an old feeler gauge and cut a .300 slot in it. Then pull the breather fitting off of the axle tube. Now you can insert the shim, hook the axle tube in the notch and measure the gap with feeler gauges. Subtract the sum of the feeler gauges for .300 and you have the wall thickness.
The barb fitting for the breather is removable?
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Unread 10-03-2008, 08:33 AM   #27
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here's something to look at.
8.8 swap/comparison

not trying to argue, i would like to see this test with aftermarket shafts for d44 s35 8.8 s88 etc..

he has a few opinions in there and he touches on c-clips.

it's not a factor for my purposes or was not when my 8.8 wasn't a super 88. personally, (in person) i have not seen a s35 or 8.8 c-clip failure. i have seen many d35 shaft failures where the shaft slides out... we all have.

really, the only thing i don't like about the 8.8 and d35/s35 is the fact that the axle shaft itself is a "wear part".
the roller bearings ride directly on the shaft. this eventually can wear and gall the shaft bearing surface. this i have seen.

was the bearing installed wrong? was it contaminated? seal compromised? i don't know for sure but have seen it a hand full of times in person on the d35 and the s35. i don't see why it could not happen on the ford 8.8 too. the super 88 eliminates the roller bearings and uses large ford 9" set 20 taper bearings with inner races much like a dana 44, they are for a ford 9"

here is a super 88 write-up for those interested in doing the upgrade (clicky-clicky). thanks to my pal stu for hosting it for me

on a side note: if anyone is interested... here's why i chose that 8.8:

i found a new one on a surplus crate for $425.00 complete.
wanted a fun project that required some skills i was rediscovering.
d-44 for tj was not readily available
my dad had a super 35 and i wanted to do something different even though he was more than satisfied with it.
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Unread 10-03-2008, 08:57 AM   #28
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Quote:
Originally Posted by never monday View Post
C-clip shafts
3 welds hold the tubes to the center (same as 35. 44 has 6)
increased tube dia = decreased ground clearance
increased casting = decreased ground clearance
none are bolt in for a TJ and require welding
offset chunk; not a big deal but won't work with a GenRight strech tank
thin cover
thiner tubes than a 35 or 44 (although the strength is about equal due to dia)
narrower track
no locker (S35 has a locker, R44 has a locker)

all can be over come. I just don't see enough strength gain to go through all the work. I do see the 8.8 as a viable, readily available axle to convert for a TJ.
Thank you, all of what you said is accurate to my knowledge. In regards to the welding of the tubes to the center: I think most everyone just does this (me included) because if you are already welding on new brackets, why not take this easy step as well. I don't think anyone is going to spin the tubes on a 8.8 behind a stock jeep 4.0 liter anyways.

In regards to not getting a locker with an 8.8. My build cost about $750 bucks (that includes the cost of the donor axle, 90 bucks at local pick-n-pull) in all and I got an upgrade in gears (from 3.73 to 4.10), disc brakes (previously had drums), and a much larger ring and pinion size. These are all upgrades that don't come with the Super 35 kit. So the tradeoff of not getting a locker is not really as big of a deal. Also included in the $750 was an $100 Riddler Diff cover I bought (which is much stronger than any thin stock unit). I decided to use the LSD that came in my Ford 8.8 for now (another upgrade from my stock Dana 35), but I have money left over to go towards buying a locker if I wanted to. A Super 35 kit costs what, 1200 bucks? I've got $750 in my 8.8. 1200-750=$450 to put towards a locker. I don't think that an 8.8 swap is "not worth the work" for what you get as you stated. That's my opinion.

In regards to an offset center: If your running 35's, most of us will have a SYE and CV driveshaft by now (as I do). The offset center works just fine, no vibes with the CV shaft. As for it not working with some gas tank skids, I didn't know that.

Thinner Tubes: As you stated above, thinner tubes is not an issue, 8.8 tubes from an explorer are 3.25" in diameter which offsets the thickness issue comparing it with a TJ Dana 35 or 44 which may have slightly thicker tube walls but smaller overall diameter.

Narrow Track: Anyone else who has performed the 8.8 swap will probably agree that the narrower track of the 8.8 is not even noticeable. I originally thought I would want wheel spacers but after I did the swap, I could barely even notice the difference with the naked eye, and there were no rubbing issues or anything with the narrower track. So, I just ran it as is.

I will go along with the other statements you made, less ground clearance, thinner cover (but who keeps the stock cover anyway). But I don't think that these are a deal breaker. The big reason you have less ground clearance under the pumpkin is because you have bigger/stronger ring and pinion over a Super 35 and Dana 44. That's reassuring to me. Just my opinion.

I will agree that the 8.8 is not a viable option for someone who can not fab or weld themselves. When you factor in labor costs for someone else doing it for you the cost can easliy grow to more than a Super 35 install or bolt in Dana 44 swap. You're are definately right on that point!

As for time spent on the swap, I probably have about 20 hours of shop time total on my 8.8 swap. Some get it done much faster, but I took my time and enjoyed the process.

Anyway, sorry it took so long to respond, I have been away from the computer for awhile. I look forward to more discussion on this.

Thanks

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Unread 10-03-2008, 09:08 AM   #29
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Originally Posted by JWitt333 View Post
have not done an axle swap as of yet and have watching and reading all the posts that i can in hopes to one day swapping my Dana 35 for something different. i can see advantages to the S35 upgrade, D44 and the 8.8, all have there pros and cons in their way. i think it is just up to the owner, his budget, skill level and time. also it makes a difference if the jeep is a DD or strictly a trail rig. all the info was very helpful. thanks for all the info and your opinions i will keep watching this thread just to educate myself on all the different options.
None of these axle ugrade options should affect daily driveability, unless you opt for the detroit locker in a Super 35. A detroit can be quirky on the road, some do it, but I wouldn't on a daily driver. A rubi Dana 44 has an electric acutated selectable locker which you can disengage for trouble free street driving, and if you get an ARB air locker with your Super 35 kit, its selectable as well. The LSD found in some 8.8's is perfectly streetable as well. Just keep that in mind when making your decision.
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Unread 10-03-2008, 09:18 AM   #30
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Originally Posted by Tim View Post



d-44 for tj was not readily available

This is a good point too. I looked for a "good deal" on a bolt in TJ dana 44 for a long time before I started my 8.8 swap. I never found a TJ dana 44 in any of the three local pick-n-pulls, and the ones for sale on the internet were all grossly overpriced in my opinion. I found my 8.8 at pick-n-pull the very first morning I went looking with everything I wanted, 4.10's, an LSD, and disc brakes. Not only that, but there must have been at least 15 other Ford explorer's with 8.8's to chose from at that same scrapyard. Just think how easy it will be to find cheap used replacement parts if and when something breaks on my 8.8 . Heck they didn't even have a TJ or any wrangler at all at any of my local scrapyards, let alone one with a Dana 44.

8.8 gets the nod for sure when it comes to easy to find and easily obtainable parts for cheap!
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