Do 3.5-4" lifts require a SYE?

chimmike

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So I'm researching various 3.5"-4" short arm lift kits. Only one so far has mentioned the possibility for needing a SYE and driveshaft.
Many of them mention nothing at all, especially some of the more expensive ones out there. So what is the general consensus, or general common experience?
Require SYE/driveshaft when lifts are that substantial? I'm hesitant on the t-case drop kits for a couple reasons: 1- t-case lever reportedly gets funky/needs cable conversion?
2) it seems to be a temporary solution and will eventually kill u-joints?

I'm not against the work involved, just need to budget it in. Unless some folks can explain why the t-case drop is sufficient for those lifts.

I plan on running no bigger than 33's.
 
2.5 inches is right around where vibes start to happen. You can mitigate it with a MML or transfer case drop or combination of both.
Anything more than that and you will definitely need an SYE. Some sites or lifts may not mention it because they don’t want to scare anyone from buying the lift but you will need to do something to get the driveline back to a decent angle.
 
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So I'm researching various 3.5"-4" short arm lift kits. Only one so far has mentioned the possibility for needing a SYE and driveshaft.
Many of them mention nothing at all, especially some of the more expensive ones out there. So what is the general consensus, or general common experience?
Require SYE/driveshaft when lifts are that substantial? I'm hesitant on the t-case drop kits for a couple reasons: 1- t-case lever reportedly gets funky/needs cable conversion?
2) it seems to be a temporary solution and will eventually kill u-joints?

I'm not against the work involved, just need to budget it in. Unless some folks can explain why the t-case drop is sufficient for those lifts.

I plan on running no bigger than 33's.
The best answer requires common sense and a clear focus on the final objective. If you don't give a shit about clearance where it matters the most, forgo the SYE and just tilt the drivetrain down by lowering the t-case and raising the motor.

If instead you plan on using the rig for something other than picking up your mochafrappalattewithanextrashotofdumbass at the local mall's fancy coffee drink drive-thru, then consider a quality SYE as a very distinct possibility.

FYI, no one that goes offroad with a tolerable level of seriousness doesn't giggle at a t-case drop.
 
The best answer requires common sense and a clear focus on the final objective. If you don't give a shit about clearance where it matters the most, forgo the SYE and just tilt the drivetrain down by lowering the t-case and raising the motor.

If instead you plan on using the rig for something other than picking up your mochafrappalattewithanextrashotofdumbass at the local mall's fancy coffee drink drive-thru, then consider a quality SYE as a very distinct possibility.

FYI, no one that goes offroad with a tolerable level of seriousness doesn't giggle at a t-case drop.

I more or less figured as much. I kinda feel that way about body lifts. I've seen mall crawlers around here with 3" body lifts, and it's the dumbest sh*t I've ever seen.

So SYE/driveshaft it is.
 
So I'm researching various 3.5"-4" short arm lift kits. Only one so far has mentioned the possibility for needing a SYE and driveshaft.
Many of them mention nothing at all, especially some of the more expensive ones out there. So what is the general consensus, or general common experience?
Require SYE/driveshaft when lifts are that substantial? I'm hesitant on the t-case drop kits for a couple reasons: 1- t-case lever reportedly gets funky/needs cable conversion?
2) it seems to be a temporary solution and will eventually kill u-joints?

I'm not against the work involved, just need to budget it in. Unless some folks can explain why the t-case drop is sufficient for those lifts.

I plan on running no bigger than 33's.
SYE and DC needed. No question at that lift height. Plus rear upper and lower CA’s. Stay at 2.5” if you don’t want to require all that
 
I have a 3" suspension lift with a MML for 4 years now and have zero driveline vibes. I don't believe everyone gets this lucky. I would never consider dropping the transfer case, looks stupid and defeats the purpose of lifting in the first place.
 
OK next question. Anything needed for spring pad on the rear axle when adjusting the control arms to angle pinion towards t-case with CV driveshaft?
 
I was going to add that adjustable upper arms are almost certainly a necessity as well, but it sounds like you already have them. I didn't need anything new or mod'd when adjusting my pinion angle, just set the arms to the right length and you're golden.
 
OK next question. Anything needed for spring pad on the rear axle when adjusting the control arms to angle pinion towards t-case with CV driveshaft?
As you rotate the pinion up, you shock body is more likely to contact the lower spring perch. Your options are to cut or grind the spring perches to clear more space or install the lower rear shock relocation mounting brackets.
 
I was going to add that adjustable upper arms are almost certainly a necessity as well, but it sounds like you already have them. I didn't need anything new or mod'd when adjusting my pinion angle, just set the arms to the right length and you're golden.
Honestly, I don't have anything yet aside from a bone-stock TJ. I'm starting with bumpers and sliders, and I've been researching suspension for a bit. I think I finally decided on a kit which is unfortunately about $1k more than I intended on spending...not including shocks or SYE.
"jeep stuff", I guess. I keep telling myself I'm doing it right the first time, this way.
Then assuming the lift doesn't work with stock wheels/tires, an immediate wheel/tire upgrade will be necessary. And I'll have to convince the wife about the necessity too. Err, shall I say CFO.
 
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Honestly, I don't have anything yet aside from a bone-stock TJ. I'm starting with bumpers and sliders, and I've been researching suspension for a bit. I think I finally decided on a kit which is unfortunately about $1k more than I intended on spending...not including shocks or SYE.
"jeep stuff", I guess. I keep telling myself I'm doing it right the first time, this way.
Then assuming the lift doesn't work with stock wheels/tires, an immediate wheel/tire upgrade will be necessary. And I'll have to convince the wife about the necessity too. Err, shall I say CFO.

I go against the grain on some aspects of this, so take this for what it's worth. I run a Zone Offroad lift, and the guys I run with have stuff like Rough Country and other "discount" components. For my purposes, I have zero complaints. I've never driven on a $3k+ lift so I can't say how much better they are, but I tend to think that the cheap stuff is absolutely usable/driveable/wheelable. I drive mine to the trails and I feel like we wheel pretty hard (it's all relative, who's to say what "wheeling hard" even means). I also tend to operate with the AWS mindset of "everything fails all the time" so spending more doesn't necessarily insulate you. The camps sort of break down like this, and both know beyond a shadow of a doubt the other camp is dumb. ;)

The cheapskate crew:
  • "sunnofabich, that might not have blown up if I had bought the more expensive part"
  • "clearly these parts were worth the 'risk' because they have held up to lots of abuse"

The buy once cry once crew:
  • "sunnofabich, I paid all that money and it still broke"
  • "clearly these parts were worth the extra expense because they have held up to lots of abuse"

Building your jeep is a journey, have fun with it, whichever camp you end up in.
 
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Yeah. I waffle day-to-day.
Day 1 "fuggit, i'm gonna overspend, piss off the wife, and probably not need something this hardcore because i'll use it once a year". Day 2 "fuggit, i'm not blowing that much money on a lift i'll put to the test once a year, the other one will accomplish what I want at a much better price."
Day 3 "is there something in between? No? Should I even bother with all this?"

Probably a good idea to re-examine how often I'll be putting the system to the test. Suffice to say if this rig ever makes it to Moab or the Rubicon in my lifetime I'll be surprised. Maybe the dollars are better spent on beefing up the Dana 35....
And the less expensive kit does allow for the ARB locker in the Dana 30 front...
 
Probably a good idea to re-examine how often I'll be putting the system to the test. Suffice to say if this rig ever makes it to Moab or the Rubicon in my lifetime I'll be surprised. Maybe the dollars are better spent on beefing up the Dana 35....
And the less expensive kit does allow for the ARB locker in the Dana 30 front...
Three questions I ask people all the time when they want to buy, or start modifying, a Jeep:

1. How committed are you to the Jeep thing? I say this because I've seen many people buy a Jeep, spend money to modify it, only to sell it 6 to 12 months down the road. If you're unsure, drive it stock for while to see if all the things, good and bad, that go along with own one are compatible with you.

2. Assuming you're confident you'll have the Jeep for the long haul, how do you plan to use it? Again, I can't count the number of times I've heard/seen people install 33" tires only to be disappointed. Either because they discover they didn't really need/use them, or that they cut corners and now have a Jeep that drives like crap.

3. How much money do you realistically want to spend? This one I ask because it may not be compatible with Question #2. You can build in stages, but have to recognize, and accept, that there are going to be trades. Some of those trades may involve buying things twice, and, if you are the "committed" type, spend more money in the long run.

The point to all this is to be honest with yourself. If you do, you'll enjoy the experience more and likely spend less money overall. This isn't the most expensive hobby, but it isn't cheap either! Just my 2¢ worth!
 
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1) This thing is more or less inherited from the in-laws. It's not going anywhere. I fully intend it to be on the road until fossil fuels are no longer available.

2) We'll drive it infrequently but will want to trailer it to locales with good trails. 33's should be no big deal assuming I set up the suspension correctly, with the correct gearing.

3) I know what I *can* spend, but that's different from what *want* to spend. Know what I mean? I'm not looking to drain the entire jeep budget on the jeep, lol. Bang for buck is important to me. The cheaper lift will do what I want, with the parts I think will be effective. They will allow me to do an air locker, and do basic black steel wheels and good tires. I can consider gears, will be able to do SYE/CV easily, and i've already got bumpers and sliders ordered/here.

This isn't my first foray into off roading. Back in 05 I built a 94 4runner. Converted to live front axle, 5.29 gears, had some fun with it. But being older, wiser, making more money, and garage space...the jeep is a nice toy I won't need to DD (and therefore worry about breaking something for fear of not getting to work on Monday). A lot of upsides to the situation now. If I had my way, I'd go long travel long arm suspension...........but I more or less promised I wouldn't hack and weld this thing. It's too mint for that anyway.
 
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I’ve had both lifts, I bought my Tj with a 4 inch Rough Country lift and t-case drop. During that time, it wheeled “fine”…then my current lift went on with a sye, what a difference. Much like you I won’t ever make it to serious places like Moab, etc, but I believe I have a perfectly capable rig for what I do.

For what it’s worth, with the drop and RC lift the Jeep didn’t have a single vibe, drove great. I didn’t realize how awful it was on a trail til after.

I like to “buy once and cry once”
 
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Whatever lift I'm doing, it won't be with a TC drop. I'm either doing the full SYE or the hack n' tap type, with a double-cardan. And whatever lift I get will have fully adjustable upper and lower rear control arms, too.
Still researching shocks, but the black magic ones have great reviews so far.
 
I more or less figured as much. I kinda feel that way about body lifts. I've seen mall crawlers around here with 3" body lifts, and it's the dumbest sh*t I've ever seen.

So SYE/driveshaft it is.

I have a 4" RC lift. After I seen the angle I opted to grab a sye kit. And just in case you are, don't be intimidated at all with it. Super easy set up.