some axles worth it or not?
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From: La Habra, CA
Year: 1988
Engine: 4.0 RENIX
I have to agree with MuscleHead, the 44 isn't much of an upgrade. The gears are a little stronger but not much (LP vs 30HP)
Wrong. the dana 44 ring gear is over 1" larger in diameter. thats a pretty big difference in strength.
see here, dana 44 vs dana 35 (so the 30 gears would actually be smaller
and the u-joints and axle shafts aren't that much larger than a 30HP.
Wrong again. the axle shafts actually use the same U joints. this is where bulletproof RCVs come in handy .
You do get rid of the wheel hubs which is one of the main advantages of it.
if you are referring to the unit bearings then yes, their removal is generally considered an upgrade
Wrong. the dana 44 ring gear is over 1" larger in diameter. thats a pretty big difference in strength.
see here, dana 44 vs dana 35 (so the 30 gears would actually be smaller
and the u-joints and axle shafts aren't that much larger than a 30HP.
Wrong again. the axle shafts actually use the same U joints. this is where bulletproof RCVs come in handy .
You do get rid of the wheel hubs which is one of the main advantages of it.
if you are referring to the unit bearings then yes, their removal is generally considered an upgrade
FIFY
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From: Wrightstown, NJ
Year: 1986 Comanche
Engine: Chevy 350
The gears are larger but you're talking about a HP 30 vs a LP 44. If we were comparing a LP 30 vs LP 44 then there is a much larger difference in strength. Bigger isn't always stronger.
Last edited by Garvin; Jul 2, 2012 at 11:25 PM.
Thread Starter
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From: Burington Washington
Year: 1989
Model: Cherokee
Engine: 4L Renix
[hijack/
i wouldn't use that term to describe the dodge diesels. while technically the Cummins is a turbocharged direct injection engine (TDI) the term TDI refers to the VW line of diesel engines. for future reference, people usually call them CTD (Cummins Turbo Diesel) or just a Dodge Cummins.
/hijack]
i wouldn't use that term to describe the dodge diesels. while technically the Cummins is a turbocharged direct injection engine (TDI) the term TDI refers to the VW line of diesel engines. for future reference, people usually call them CTD (Cummins Turbo Diesel) or just a Dodge Cummins.
/hijack]
" . but if people wanna mix that up with a vw go ahead there's also CDI diesels as well. that cummings also used on the early 24v TD they produce. before going on to TDI.i'll remeber to say the ctd in future tho.
Last edited by Oxen__; Jul 2, 2012 at 11:27 PM.
CF Veteran
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From: La Habra, CA
Year: 1988
Engine: 4.0 RENIX
TDI is a specific injection type engine family like IDI is "wich you understand " . but if people wanna mix that up with a vw go ahead there's also CDI diesels as well. that cummings also used on the early 24v TD they produce. before going on to TDI.
i'll remeber to say the ctd in future tho.
" . but if people wanna mix that up with a vw go ahead there's also CDI diesels as well. that cummings also used on the early 24v TD they produce. before going on to TDI.i'll remeber to say the ctd in future tho.
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Ive run a low pinion 44 5.38 gearset on larger tires, and was arguably harder on it over the people i wheeled with. I went through one gearset in 5 years while seeing many hp30 gearsets come and go. I like to think housing stiffness has something to with that as well as axle shaft deflection when under a load, as my 44 shafts and u joints always seemed to hold up better than guys running smaller tires and dana30s.
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From: La Habra, CA
Year: 1988
Engine: 4.0 RENIX
wrong as well. the difference between HP30 and a LP30 are minimal. yes HP is slightly stronger because HP gears are reverse cut, but the "the pinion gear rides on the weaker side of the ring gear" argument is invalid for the D30 because they are 2 different gear sets. plus, why is it that almost every solid axle vehicle runs a LP rear axle instead of a HP? by your logic, jeeps should have come with HP dana 30s front and rear. yet we see low pinion axles used in the rear consistently. also, the highly sought after rear XJ dana 44 is, you guessed it, low pinion.
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From: Lantana, Fl
Year: 1996
Model: Cherokee (XJ)
Engine: 4.Slow
Originally Posted by CheapCherokee
wrong as well. the difference between HP30 and a LP30 are minimal. yes HP is slightly stronger because HP gears are reverse cut, but the "the pinion gear rides on the weaker side of the ring gear" argument is invalid for the D30 because they are 2 different gear sets. plus, why is it that almost every solid axle vehicle runs a LP rear axle instead of a HP? by your logic, jeeps should have come with HP dana 30s front and rear. yet we see low pinion axles used in the rear consistently. also, the highly sought after rear XJ dana 44 is, you guessed it, low pinion.
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From: Wrightstown, NJ
Year: 1986 Comanche
Engine: Chevy 350
wrong as well. the difference between HP30 and a LP30 are minimal. yes HP is slightly stronger because HP gears are reverse cut, but the "the pinion gear rides on the weaker side of the ring gear" argument is invalid for the D30 because they are 2 different gear sets. plus, why is it that almost every solid axle vehicle runs a LP rear axle instead of a HP? by your logic, jeeps should have come with HP dana 30s front and rear. yet we see low pinion axles used in the rear consistently. also, the highly sought after rear XJ dana 44 is, you guessed it, low pinion.
First and foremost the importance is in terms of ring and pinion strength. When a low pinon axle is used on the front position of a fourwheeldrive vehicle, the ring gear is spun backwards. This is important because the ring gear teeth are curved. A simple geometry lesson tells us the convex side is stronger because the load is equally distributed throughout the length of the tooth. This can be verified by comparing the ring gear tooth to a dam holding back a lake. The convex side goes towards the load. The high pinion axle uses a reverse cut gear, and when used in a front position, the convex side becomes the drive side again, and the concave side becomes the coast side. Consequently, a high pinion axle located in the rear position of a vehicle is spinning backwards, and again the strong side of the tooth and the weak side of the tooth are switched.
Is there any other advantage to a high pinion? Yes, another advantage is that the driveshaft location tends to be noticeably higher because it is above the centerline of the ring gear, as much as 4-5" higher in some vehicles. This can be an advantage where ground clearance is important, and also a better driveline angle can be acheived. This can be especially important on shorter front driveshaft vehicles such as Jeep ZJ's and XJ's, which tend to devolop driveline vibrations when lifted above 4" with a low pinion front axle.
Is there any other advantage to a high pinion? Yes, another advantage is that the driveshaft location tends to be noticeably higher because it is above the centerline of the ring gear, as much as 4-5" higher in some vehicles. This can be an advantage where ground clearance is important, and also a better driveline angle can be acheived. This can be especially important on shorter front driveshaft vehicles such as Jeep ZJ's and XJ's, which tend to devolop driveline vibrations when lifted above 4" with a low pinion front axle.
Ive run a low pinion 44 5.38 gearset on larger tires, and was arguably harder on it over the people i wheeled with. I went through one gearset in 5 years while seeing many hp30 gearsets come and go. I like to think housing stiffness has something to with that as well as axle shaft deflection when under a load, as my 44 shafts and u joints always seemed to hold up better than guys running smaller tires and dana30s.
For the OP...If you really want to go through with all the work going from HP30 to a LP44, be my guest, but I don't see enough strength gains to warrant all the work. If you want to go tons then I say save up and go tons, I don't regret it one bit and am actually glad I skipped the middle step. Keep in mind that putting a front axle in is a lot of work.
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From: LI, NY
Year: 1998
Model: Cherokee
Engine: 4.0, bolt ons for days...
You haven't seen Sam wheel I guess
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Last edited by ktmracer419; Jul 3, 2012 at 11:14 AM.
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From: +34° 25' 35.67", -81° 21' 12.04"
Year: 1993
Engine: 4.0
Why is it? Invest money and time to only be able to run a couple inch taller tire over the 35s that his stock setup is handling. i mean cmon. If he has even thought about 38s he should just do ton axles and be done with it. Once you get into that big of a tire then its 40s next 
Awww did i hurt your waggy 44 feelings
. No right or wrong with opinions 
Awww did i hurt your waggy 44 feelings
. No right or wrong with opinions I'm hurt, I can't hold back the waterfall from my eyes. Oh my, how will I ever go on.
I swear. You and that damn facebox thing.
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From: +34° 25' 35.67", -81° 21' 12.04"
Year: 1993
Engine: 4.0
But arguing the difference between a Dana 30 and Dana 44 are much more entertaining.
I'd bet my itty bitty LP44 would run 38's no problem.
After all, it's only a D44.
I once met a guy that took a set of D44 shafts, slid them into his D30 housing, welded them to the side gears in the diff, turned down the outer shaft and slid it into the unit bearing and welded it solid. Worked like a champ!
For about 10 minutes.
I'd bet my itty bitty LP44 would run 38's no problem.
After all, it's only a D44. I once met a guy that took a set of D44 shafts, slid them into his D30 housing, welded them to the side gears in the diff, turned down the outer shaft and slid it into the unit bearing and welded it solid. Worked like a champ!
For about 10 minutes.
Thread Starter
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From: Burington Washington
Year: 1989
Model: Cherokee
Engine: 4L Renix
my amount of lift will only be 5.5-6 inches total. that being said could i get away with running low pinion diffs? snow isnt terribly hard on your rig. i wheel like a pansy too. i like going slow and i never rush. those ways have done me well so far.
i'm moving my rear axle back five inches and my front axle forward two inches. and probably clock the t-case down a little for the front drive line. i'm probly going to go all leaf srings front and rear. there cheap and can be set up pretty well. using chevy 64's froma 3/4 or 1/3 ton truck.
thats the build concoction i am thinking.
i'm moving my rear axle back five inches and my front axle forward two inches. and probably clock the t-case down a little for the front drive line. i'm probly going to go all leaf srings front and rear. there cheap and can be set up pretty well. using chevy 64's froma 3/4 or 1/3 ton truck.
thats the build concoction i am thinking.
