Driveshaft question - 1350's too much for 5.38 gearing?
- Thread starter bones37
- Start date
NevadaZielmeister
Caught the Bug
I am not sure what the OP is getting to, but I am running JE Reel 1350 driveshafts front and rear with 5.38 gearing and so far, no issues at all.
What is the concern?
What is the concern?
swampdog
New member
I think is concern is making the R&P the weak point the the setup rather than a u-joint or shaft. I don't believe this would be an issue in his case, but I think this is what he is getting at.
bones37
Member
The concern is with the smaller pinion size and stronger joint of the 1350. I know the 1310 vs 1350 debate goes back and forth. I was set on a 1350 replacement, but would rather replace a u-joint with a 1310 than have a more costly differential repair.
My question comes back to the pinion size and if there is a rule of thumb in relation to the strength of the driveshaft joints. I'm on heavy 37's and like the rocks.
My question comes back to the pinion size and if there is a rule of thumb in relation to the strength of the driveshaft joints. I'm on heavy 37's and like the rocks.
bones37
Member
Yep, you beat me to it!
Personally, 5.13's is the highest ratio I'd recommend for a Dana 44 and specifically because the pinion on a 5.38 is really really small. That being said, I personally think it's foolish to run anything less than a 1350 shaft as a 1310 is simply too weak for 37's and any hard play. It's not just the u-joints that are small and weak, it's the yokes as well. My friend Jesse blew his 1310 output shaft yoke on the Rubicon a couple of weeks ago and he's only running 35's.
bones37
Member
You nailed it on the head. That's my predicament! I've been running the 5.38's for 3 years without issue (knock on wood). It didn't take long for me to wish I had gone to 5.13's for future considerations (like the one I'm in now), although the 5.38's have served me well. I don't want to regear just to upgrade my driveshafts. I also don't want to downgrade the strength of the driveshaft either.
It sounds like the 1310 may be the safest (read: cheapest) for now with the expectation for failure until I upgrade axles. Axle replacement may be well into the future though as they have held up well with their own upgrades.
It sounds like the 1310 may be the safest (read: cheapest) for now with the expectation for failure until I upgrade axles. Axle replacement may be well into the future though as they have held up well with their own upgrades.
I personally would NOT recommend 1310's PERIOD. They are cheaper for a reason and depending on how you play, they'll break well before you would ever break a 5.38 pinion. I would STILL recommend a 1350.
LarryG
New member
Even with a 44 and 410 gears? Running 35s.
The one and ONLY u-joint a JK comes with from the factory is on the front drive shaft and at the pinion flange. This joint is a 1330. In other words, it's BIGGER and STRONGER than a 1310 and it was designed for use with 32" tires. Do you really want to run a WEAKER u-joint and yokes with a bigger set of tires?
GraniteCrystal
New member
That's really interesting to me. I'd heard to run a 1310 so my driveshaft (easy to replace, not super expensive) is the weakest part of the system. But you're saying to run a 1350 and that will still be the case, it just won't break as easily.
Well, I don't know where you "heard" that from but you're more than welcome to trust what they have to say. Me, what would I know.
What I'm saying is that I don't understand why anyone would want something to break more easily than a factory drive shaft. Ideally, I personally don't want anything to break and to the best of my ability, I try to build my Jeeps accordingly.
GraniteCrystal
New member
Thanks Eddie. Just clarifying your point. I agree: ideally nothing breaks. Just making sure I'm understanding you correctly. When running 37s on D44s with 5.13 gears and 1350 driveshaft, what's the weakest point? Thinking the two contenders are the pinion or the driveshaft. Thinking about it wrong?
Thanks for helping a newbie understand.
37's on Dana 44's running 5.13 gears and driven by a 1350 shaft is a pretty strong setup. You're more likely to break a front drive shaft u-joint or bend a rear axle flange then to break either the shaft or ring & pinion. It's a setup that I prefer and one that's worked well for me in the past.
GraniteCrystal
New member
Awesome. Thank you sir.
TonyViv
Member
Just curious...... what is the rezzpa joint strength equal to? without the binding/angle issues associated with a lift ....And if factory is a 1330 strength, why are the aftermarket companies even doing a 1310? Ease of parts?
Or is a 1330 equivalent ujoint not even available?
Or is a 1330 equivalent ujoint not even available?
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JoeB-JKURX
New member
You are actually worse off with the 4.10s and 35s than you would be with 5.13 or 5.38 and 37s. The load on the driveshaft is proportional to the size (radius) of the tires and inversely proportional to the gear ratio (running a higher ratio reduces the load). With 4.10s and 35s you are probably already past the design limit of the 1310s (as was pointed out, stock is a 1330). You would be right at the same loading as stock with 37s if you had a 4.88 ratio. The 5.13 is great for 37s to account for the heavier tires and increased weight of a built Jeep. 5.38s are overkill IMO.