Who has had the Dana 30 in their JK fail?
- Thread starter harv3589
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HAFICON
Adventurer
I did have the tubes on mine start bending with very little wheeling on 35's. Had it trussed, re-geared, ARB and all the work that it should have needed... And the ring and pinion exploded... I upgraded to a D44 Pro Rock Unlimited and no issues... I will try to post pictures of the damage..
The stock D44 has the same tubes and C's as the D30 only big difference is the ring and pinion in the D44 are going to be better... If you can swing it go with an aftermarket D44 I went Pro Rock 44 Unlimited because they have the thickest walled housings on the market. They say you can run up to 40 inch tires on their I modified housing but I will stick to 35s...
The stock D44 has the same tubes and C's as the D30 only big difference is the ring and pinion in the D44 are going to be better... If you can swing it go with an aftermarket D44 I went Pro Rock 44 Unlimited because they have the thickest walled housings on the market. They say you can run up to 40 inch tires on their I modified housing but I will stick to 35s...
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Happy Joe
Apprentice Geezer
Dana 30s have always been a less strong axle for street vehicles on relatively small tires. while they can , with care survive moderate trails and tires in the 35 inch range even the newer (post 1995 versions are less than robust.
Dana 44s have always been stronger than D30s overall, however, they too have historically met there match in tire sizes over 36 inches with high traction tires on difficult trails especially in vehicles heavier than a light SUV. The bigger ring and stronger pinions used in the more modern versions are stronger than the old school models but rings and pinions are only part of the strength equation.
There is a reason for Dana 60s and 14 bolt differentials in larger trucks and as the preferred differentials in the harder core, harder driven, vehicles with tires over 38 inches.
That said an educated right foot with careful line and tire selection can enable even old school (weaker) D30s to live with 35s on difficult with some very difficult (not extremely, extreme trails).
To really enjoy less stressful four wheeling on the more technical trails, IMO, the powertrain needs to be upgraded to match the: trails, engine, gearing, driving style and tires.
... its simple weak link elimination 101 ... and not particularly expensive if done yourself.
Enjoy!
Dana 44s have always been stronger than D30s overall, however, they too have historically met there match in tire sizes over 36 inches with high traction tires on difficult trails especially in vehicles heavier than a light SUV. The bigger ring and stronger pinions used in the more modern versions are stronger than the old school models but rings and pinions are only part of the strength equation.
There is a reason for Dana 60s and 14 bolt differentials in larger trucks and as the preferred differentials in the harder core, harder driven, vehicles with tires over 38 inches.
That said an educated right foot with careful line and tire selection can enable even old school (weaker) D30s to live with 35s on difficult with some very difficult (not extremely, extreme trails).
To really enjoy less stressful four wheeling on the more technical trails, IMO, the powertrain needs to be upgraded to match the: trails, engine, gearing, driving style and tires.
... its simple weak link elimination 101 ... and not particularly expensive if done yourself.
Enjoy!
I wasn't planning on changing out my Dana 30 but changing some of it and strengthen it some....
Trusses, gussets and axle sleeves to help with the bending people say can occur. Eventually RCV axles...sooner than later regear to 4.56 I think and a trutrac.
I'm not a hard core off roader so not worried too much about it...not so much into the mud and rocks as running cool trails for the scenery.
Just so much talk about the 30 being fragile it seems that I wanted some real life input on who has had failures. The tubes and C's on the 30 are the same as the 44...so I would think if u bend a 30 you would have bent a 44.
Trusses, gussets and axle sleeves to help with the bending people say can occur. Eventually RCV axles...sooner than later regear to 4.56 I think and a trutrac.
I'm not a hard core off roader so not worried too much about it...not so much into the mud and rocks as running cool trails for the scenery.
Just so much talk about the 30 being fragile it seems that I wanted some real life input on who has had failures. The tubes and C's on the 30 are the same as the 44...so I would think if u bend a 30 you would have bent a 44.
You should have no issues Harv. I have 189,000ish on my D30 running 33" tires, off roading ALOT, whenever we get the chance actually. I would say that more than half of my KMs are off road. We do not take it easy, but we are not dumb and don't hammer it. I have had zero issues other than an axle seal. Mine will be replaced with teraflex grease seals this spring. I am also putting in true tracs as well. piece of mind more than anything.
Happy Joe
Apprentice Geezer
I agree; with more than 33 years of trails and highways behind my current front D30 conservative driving and conservative tires (it met its match with 14" wide 33" Boggers on rocks but works pretty well with conservatively driven, medium traction, 35" BFG mud tires). It still works well and is still straight without the need of trusses or other accessories... I couldn't guess at the miles as it has been used in 3 vehicles, though mostly with 33 inch tires.
After witnessing and participating in more than a little breakage, my opinion is that its cheaper and better to go with axles that are stronger than you need, before you need them (a modern D30 is more than enough for normal 33 inch tires, IMO).
I would not worry about the C's and unless you want to jump it or are an adherent to the ram and slam/bulldozer school of off road driving.
Bending of axle tubes is typically done by jumping the vehicle or other ill considered driving techniques (seen the aftermath never done it).
We (several friends and I have run multiple Post 1978 OEM, SUV (not the truck HD version), D44s in Jeeps and some light pickups on very difficult to extreme trails and never bent a tube nor hurt a C, nor ran a truss; this includes running with; 5.88 gears, Air lockers or Detroit lockers up to 38 inch super swampers in semi extreme mud, snow, gravel, sand and rocks with engines ranging from injected 4 liters through fuel injected 460 engines the only axle damages were a couple of ujoints and some stub shafts... however the axles were well set up and the vehicles were competently driven.
...Personally; with 33s and A modern Dana 30 and probably a modern Dana 44 I believe you are good to go...I wouldn't worry!
Enjoy!
After witnessing and participating in more than a little breakage, my opinion is that its cheaper and better to go with axles that are stronger than you need, before you need them (a modern D30 is more than enough for normal 33 inch tires, IMO).
I would not worry about the C's and unless you want to jump it or are an adherent to the ram and slam/bulldozer school of off road driving.
Bending of axle tubes is typically done by jumping the vehicle or other ill considered driving techniques (seen the aftermath never done it).
We (several friends and I have run multiple Post 1978 OEM, SUV (not the truck HD version), D44s in Jeeps and some light pickups on very difficult to extreme trails and never bent a tube nor hurt a C, nor ran a truss; this includes running with; 5.88 gears, Air lockers or Detroit lockers up to 38 inch super swampers in semi extreme mud, snow, gravel, sand and rocks with engines ranging from injected 4 liters through fuel injected 460 engines the only axle damages were a couple of ujoints and some stub shafts... however the axles were well set up and the vehicles were competently driven.
...Personally; with 33s and A modern Dana 30 and probably a modern Dana 44 I believe you are good to go...I wouldn't worry!
Enjoy!
If you remain concerned, one potential solution is to watch Craigslist for a take-off axle. Thank you to the guys who believe that the Pro-Rock 44 or 60 is the only possible answer to an axle, 30 take-offs are available on a fairly regular basis at comparatively good prices. As a side note, Rubicon model 44s with lockers also pop up from time to time.
I pick up stuff like that when I find a great deal, but I have storage space. you get a full set of spare parts and can swap an axle generally much faster than you can rebuild one on the vehicle.
Yes, you still break stuff and get towed off the trail, but the learning experience is much less stressful when you have spares at home!
I pick up stuff like that when I find a great deal, but I have storage space. you get a full set of spare parts and can swap an axle generally much faster than you can rebuild one on the vehicle.
Yes, you still break stuff and get towed off the trail, but the learning experience is much less stressful when you have spares at home!
I have been preaching this for years. EVERYONE is like D30 is a wet noodle, crap, junk, its going to break and bend if you hit a sand pebble on the pavement. In reality, if your not a meatball behind the wheel and run 33's you should be fine if you take your time and treat your rig with respect.
shawnr
New member
Timely thread. I just moved from a 2" BB to a 3" Zone lift. Been running 33's (Wrangler Duratrac's) and want to move up to 35's. So, I had the D30 sleeved and gusseted. Now after reading this thread, I'm concerned about moving up to 35's. I have 4:10 gears and thought I'd be ok on 35's. Not as good as 4:88 but adequate for my 3.8L. However, after reading a few of the comments, I'm wondering if I should stay with 33's. I'm not a hard core off-roader. I just enjoy going on trails and viewing the scenery.
You will be more than fine. Just use your head! I have a friend who runs 35's on his stock D30, He hammers the piss out of it and has a set of mattrax in the winter for it. He's bombing through the wilderness in winter on tracks and does not have an issue with his D30. All he changed was he added lockers because in deep snow the tracks would cause the open diff to spaz out and toss him one way or the other. Now with the lockers, he just blasts over cutovers, hill sides etc!
comptiger5000
Adventurer
I've seen a WJ wheeled fequently on 37s with a D30 and the stock aluminum 44a for a few months before the guy swapped in bigger axles. Never broke a shaft or anything. The D30 isn't indestructible, but if you're not getting air time and you're reasonable about how you treat it, it's not going to just explode as soon as you hit dirt.
I've been running 35s on my dana 30 for over 50k miles and I run 37s when I know that I'm going wheeling. I sleeved the axle, added c gussets and switched to chromoly shafts and have not had a problem. I also regeared to 4.88 and added a locker. I have a JKU that weighs more than 5000 pounds and I wheel it on a regular basis. My biggest issue is how fast it wears out ball joints.