A couple questions regarding sye/ds and gearing

Reidminer

Reidminer

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Jan 9, 2019
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Hi everyone, so I’ll get right to the point. I’m going to be doing a sye and driveshaft real soon as my next project, and after reading through some other threads it brought up a question. Currently I’ve got a 4in suspension lift, with non-adjustable control arms. When I do the sye/ds, will I need to correct my drive angles(I.e needing adjustable control arms?) or is that only if I want to get rid of the 1in t-case drop along with the install of the sye/ds?

Second question...I just took my rig off road for the first time since I bought it in October. It’s a 4.0 manual on stock gears and axles(01 tj so 3.73’s and Dana 30/35) running 35x12.5’s. I noticed while out on the trails that at very low speeds in 4lo, pretty much any pressure to the gas pedal resulted in a rather jerky acceleration, like it was lunging forward. I’m guessing that’s from the improper gear ratio? 4hi was definitely better but I could feel at times while giving it just enough gas to crawl it would sometimes bog down(which I’m sure is partially normal, and I would give it more gas in that case).
So my question is, is it worth it to regear my current axles? Also, if I regear, and then further down the line want to build these axles up(stronger housing, better shafts etc) would I be able to do that separate from the regear? After wheeling for the first time yesterday in it, I’m in love and can’t wait to get back out there, but I want it to be as enjoyable as possible, and I’m all about improving my rig. So would it be worth it to regear soon(so I can wheel more comfortably for the next year or two(while I save to build the axles)?
 
Lower gears would actually make things worse. You just need to get your foot trained for low range throttle control.
 
It is best to do the axle upgrades all at once. Lockers, Super 30 kit, and Super 35 kit should all be done at the same time to minimize overall costs. Selectable lockers would be the most expensive option, but give you the most versatility.

Doing gears and carriers separately will cost you on the order of $1000 extra in labor. Every time the carrier is changed, the gears have to be reset. Likewise, every time the gears are changed, the carriers must be removed and reinstalled. Every time the spline count of the axle shaft changes, the carrier must change, and the gears must be reset.

The Super 30/35 should be more than strong enough for 35s, unless you are doing very extreme things.

If you have a 97-04, you would want 5.13 gears. (4.88 for 05-06.) 5.13 is the deepest you can go with those axles.
 
As for the jerking, consider adding a hand throttle. A hand throttle is basically a bicycle shifter mounted on the shifter that is hooked up to the throttle bracket. Simply pull it a few clicks and it will hold the RPMs up so you can have a foot on the clutch and a foot on the brake at the same time. Since it is set, you won't have any jerking like you would with your foot on the gas pedal. Hand throttles are cheap ($40 or less) and only take an hour or two to install.

https://www.quadratec.com/products/16192_250.htm
 
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Reidminer said:
When I do the sye/ds, will I need to correct my drive angles(I.e needing adjustable control arms?) or is that only if I want to get rid of the 1in t-case drop along with the install of the sye/ds?
Click to expand...
When you install the SYE, the skidplate will no longer need to be lowered. You can reattach the skidplate to the frame as the factory had it.
Once the skidplate is back in its factory location and your adjustable control arms are installed you will need to adjust your pinion angle to match the transfercase output yoke.
 
CodaMan said:
Lower gears would actually make things worse. You just need to get your foot trained for low range throttle control.
Click to expand...
Really? Isn’t that the one of the main reasons to regear? To gain back all the lost abilities when going to 35’s? Like 5th is useless and had always heard and read that going to 4.88’s or higher would allow for better low gear driving
 
Fouledplugs said:
When you install the SYE, the skidplate will no longer need to be lowered. You can reattach the skidplate to the frame as the factory had it.
Once the skidplate is back in its factory location and your adjustable control arms are installed you will need to adjust your pinion angle to match the transfercase output yoke.
Click to expand...
Okay, so I am correct in assuming I will need to replace all the control arms with adjustable ones? Is this something I can do spread out? Like do the sye/ds, run it with the dropped skid plate for a month or two then do the control arms?
 
Steel City 06 said:
It is best to do the axle upgrades all at once. Lockers, Super 30 kit, and Super 35 kit should all be done at the same time to minimize overall costs. Selectable lockers would be the most expensive option, but give you the most versatility.

Doing gears and carriers separately will cost you on the order of $1000 extra in labor. Every time the carrier is changed, the gears have to be reset. Likewise, every time the gears are changed, the carriers must be removed and reinstalled. Every time the spline count of the axle shaft changes, the carrier must change, and the gears must be reset.

The Super 30/35 should be more than strong enough for 35s, unless you are doing very extreme things.

If you have a 97-04, you would want 5.13 gears. (4.88 for 05-06.) 5.13 is the deepest you can go with those axles.
Click to expand...
Gotcha okay, thanks for the in depth reply! Definitely makes sense when you explain it out that way. And thanks for the tip on the hand throttle. That will definitely help with that issue until I can do the axle build. So with 5.13’s, will that improve low gear/range usage? Am I correct in thinking that a gear set like 5.13’s will help low range as well as use of gears on the highway?
 
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Reidminer said:
Really? Isn’t that the one of the main reasons to regear? To gain back all the lost abilities when going to 35’s? Like 5th is useless and had always heard and read that going to 4.88’s or higher would allow for better low gear driving
Click to expand...

Not for a sensitive throttle. Think of it this way ... you said all was fine in high range, but sensitive in low range. Installing lower gears would make low range even lower, so even more sensitive. It's all about throttle control.
 
Reidminer said:
Gotcha okay, thanks for the in depth reply! Definitely makes sense when you explain it out that way. And thanks for the tip on the hand throttle. That will definitely help with that issue until I can do the axle build. So with 5.13’s, will that improve low gear/range usage? Am I correct in thinking that a gear set like 5.13’s will help low range as well as use of gears on the highway?
Click to expand...
It will help both situations.

It will give you extra low options in low range, and also allow you to use high range on some very basic trails. It will also keep your RPMs much closer to the torque band on the highway. In a lot of cases, eliminating lugging increases fuel economy as well. The lower torque demands on the drivetrain will also help protect all of its components.

Here is a basic guide to help select a gear ratio:
https://wranglertjforum.com/threads...angler-tj-lj-and-other-re-gearing-faqs.17063/
Check out this calculator to determine how much of an effect various gear ratios have:
http://www.grimmjeeper.com/gears.html
To give you a basis for comparison, a stock TJ Rubicon with NSG370 does about 2700 RPM at 70 mph (0.84 OD, 30.5" tires, 4.10 gears). The TJR with 6 speed is the deepest factory gearing ever offered on the TJ. 5.13 gears bring you very close to that overall gearing RPM range with a 5 speed and 35s.
 
Steel City 06 said:
It will help both situations.

It will give you extra low options in low range, and also allow you to use high range on some very basic trails. It will also keep your RPMs much closer to the torque band on the highway. In a lot of cases, eliminating lugging increases fuel economy as well. The lower torque demands on the drivetrain will also help protect all of its components.

Here is a basic guide to help select a gear ratio:
https://wranglertjforum.com/threads...angler-tj-lj-and-other-re-gearing-faqs.17063/
Check out this calculator to determine how much of an effect various gear ratios have:
http://www.grimmjeeper.com/gears.html
To give you a basis for comparison, a stock TJ Rubicon with NSG370 does about 2700 RPM at 70 mph (0.84 OD, 30.5" tires, 4.10 gears). The TJR with 6 speed is the deepest factory gearing ever offered on the TJ. 5.13 gears bring you very close to that overall gearing RPM range with a 5 speed and 35s.
Click to expand...
Awesome thanks again!! Yeah that’s what I had thought I had read before about gearing. I’ll definitely checkout the calculator.
 
Fouledplugs said:
You just need to get out and practice. Getting used to the throttle takes time. You will evetually get used to it and it will become a non-issue.
Click to expand...
I definitely don’t dispute that! Haha. I could tell I can improve greatly in that area. However, I think proper gears and a hand throttle are a good way to go anyway, especially with a manual trans
 
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