Rear pinion angle

[WILDHOBO]

Fractions, not multiple inches. Pretty easy to pencil out if one knows the length of the control arm and how far down one end swings. One can also calculate the amount the pinion would "tip" based on the differences of the lengths of the control arms (upper vs lower)

Good to know 1/4" will help me get over that next boulder - maybe taller tires would make some difference, too LOL (and look better with that big a lift)

Hey, are we now picking nits? I wonder if John Deere makes a nit picker.

If they did, it would only be serviceable at a dealer.

Sponsored

 

[WILDHOBO]

Sorry I’m not not good at this or explaining. I want the drive shaft to be pointed at the center of the pinion hole not coming in at an angle. Yes the front of the Jeep is super low in this picture. Does that affect what I’m looking at? I’m installing the lift on the front as we speak and will report back when all done how things are looking. I just want to be able to safely drive this to an alignment shop without chewing up something.

I drove mine with the rear angle very similar to that for 5k miles before I corrected it. You’ll be fine. You’re doing just fine at explaining. My rear lift is around 4.5”, and I drove it from April till July before adding adjustable control arms. A carrier bearing spacer will help a decent amount, is cheap, and easy to install. Dana Spicer recommends them for lifts over 2”. And im referring to the rear. The front doesn’t do a thing to the rear. Just put it on the ground and tighten everything. You can’t adjust the pinion angle without a bearing spacer or adjustable control arms. There is no other way.

 

[Pescatoral Pursuit]

Depends on the driveshaft, but a lot. My suggestion is assuming you’re happy with your current rear axle position in the wheel well. Mine is really close to dead center.

I see a lot of lifted jeeps where the tires are cheated to the center of the vehicle.

Mine has fixed CAs so there not much to do with this lift but if I wanted to go higher, would definitely appreciate enough driveshaft slack to center the wheels in their spaces.

 

[ducatijosh]

I drove mine with the rear angle very similar to that for 5k miles before I corrected it. You’ll be fine. You’re doing just fine at explaining. My rear lift is around 4.5”, and I drove it from April till July before adding adjustable control arms. A carrier bearing spacer will help a decent amount, is cheap, and easy to install. Dana Spicer recommends them for lifts over 2”. And im referring to the rear. The front doesn’t do a thing to the rear. Just put it on the ground and tighten everything. You can’t adjust the pinion angle without a bearing spacer or adjustable control arms. There is no other way.

Well I do have all 8 adjustable control arms. I guess what’s annoying is I’ve measured and installed them to the exact lengths specified for a 2.5” lift by Clayton. I don’t understand why I’m so far off given they’re set per the instructions

Is it because the springs are new and haven’t settled in yet? Maybe If they drop half an inch it’ll be right ?

Will loading the bed with weight affect the angle?

 

[ShadowsPapa]

Well I do have all 8 adjustable control arms. I guess what’s annoying is I’ve measured and installed them to the exact lengths specified for a 2.5” lift by Clayton. I don’t understand why I’m so far off given they’re set per the instructions

Is it because the springs are new and haven’t settled in yet? Maybe If they drop half an inch it’ll be right ?

Will loading the bed with weight affect the angle?

IMO, any time someone says "adjust control arms" or whatever the part may be, it's a starting point, not the end of the road, now it's perfect, measurement. It's a place to start from, home base.
They may see it differently, but a lift will change the vehicle height DIFFERENTLY on different Jeeps. If I put that same lift on an Overland, it would lift it higher and I'd need to adjust things differently. That lift on your Rubicon will lift YOUR Rubicon differently than the Rubicon owned by another person based on the weight of the vehicle (mostly).
That's why there are so many different factory stock spring numbers - to account for the varying weight of the vehicles.
I have literally measured a half dozen other Overlands on dealer lots - they all were the same number center of hub to fender flare trim, and yet each had different spring numbers and rates.
So when they say "3.5" lift" that's based off a very specific vehicle weight. Your lift height in the end may vary.
I've seen guys put "rubicon springs" other other Gladiators and some say they got a .75" lift while others got 1.25" lift - that's a half inch difference.
So don't get hung up on numbers - start there, adjust as you need to for your truck with that lift.
And yes, weight will change things, however, not a lot unless you max the thing out and then some. These are made to operate safely and fine at curb height, and at rated load load height.
How much yours drops with weight in the back will vary as well. No one can say "with 1,000 pounds your truck will drop exactly 2.5" " because your truck unloaded will have a slightly different weight.

In the end, don't get hung up on numbers and details -do what's needed to get to where you need to be. May be more, may be less, than what the next guy had to do, but they can still help aim you in the right direction.

 

[Lunentucker]

I'd call that epic fail.......

Various CV joints can handle a heck of a lot more angle and don't need to be matched end for end, but they also have limits - isn't it somewhere in the 30s as far as degrees? Memory failing..........

The rubber seal failed and it dumped the grease. Weakest link theory.

 

[ShadowsPapa]

Everyone read “pinion angle” and hyper focused on that.

Not everyone. I read pinion angle as compared to stock, and in relationship to the frame. That's why I measure with tools that don't care how far up or down the car or truck is pointed.
Pinion angle is a relationship, not a hard solid number compared to the horizontal plane of the ground. You can run a pretty steep pinion angle compared to the horizon as long as the rest of the driveline relationship is accounted for.
I compare the pinion to the driveshaft when I talk pinion angle, or to the frame in some cases.

I ran a hell of a rake on one of my cars to account for street-strip tires and squat on take-off, and I ignored that completely when setting up the differential and driveshaft.

 

[ShadowsPapa]

The rubber seal failed and it dumped the grease. Weakest link theory.

For some reason that seal seems to be rather important. Not only loss of grease, but entrance of dust which will rip those things apart real fast. What little grease remains is abrasive like valve lapping compound.

I check the boots on all axles and shafts on all three of our vehicles equipped with CV joints on a fairly regular basis. They flex a lot, and that flexing makes them get warm, that and age - crack, rip, loss of grease, entrance of dust, catastrophic failure.

You should see the underside of one of my cars after the rear joint failed - severe angle, then the torque forced the pinion up further and snapped the rear joint. Man, what a mess. But it's better than a front joint failing, I guess.

 

[ducatijosh]

So when I’m all done should I just drive it to the alignment shop like this or lengthen the upper rear control arms to straighten out the driveshaft / pinion first?

 

[ShadowsPapa]

Whether the angle is “poor” or not is not what OP asked. You’re saying on an incline (we’ve discussed this earlier today) where the nose is pointing down, the pinion won’t also be pointing down?

OP please wake up and clarify your question for us LOL

I (and likely you?) sure hope he's not judging anything by the rake of the truck. Heck, park it in my yard and depending on where you park, the pinion will be either pointing up a lot, or down a lot.
IF he's concerned, put a jack under the front, level the truck, and ask again, eh?

 

[WILDHOBO]

So when I’m all done should I just drive it to the alignment shop like this or lengthen the upper rear control arms to straighten out the driveshaft / pinion first?

Not in my opinion. They won’t do as well as you do. Control arms are easy to get right because you’re dealing in either full 180 or 360 degree turns and thread counts. Based on what I saw in your picture, I’d shorten the lowers and lengthen the uppers, both by the same amount, and from experience, I’d start with 1/4”.

 

[jav_eee]

I (and likely you?) sure hope he's not judging anything by the rake of the truck. Heck, park it in my yard and depending on where you park, the pinion will be either pointing up a lot, or down a lot.
IF he's concerned, put a jack under the front, level the truck, and ask again, eh?

well now it appears to me as though he’s concerned about the driveshaft angle. But the coffee is still soaking in so maybe I’m wrong.

I want the drive shaft to be pointed at the center of the pinion hole not coming in at an angle

 

[ShadowsPapa]

So when I’m all done should I just drive it to the alignment shop like this or lengthen the upper rear control arms to straighten out the driveshaft / pinion first?

In my OPINION, I'd level it out some - take out some of the angle between the drive shaft and pinion. Those joints will handle it but you are better off starting more neutral. If it was mine, I'd up the nose of the differential.
I am ONLY looking at the pinion as it compares to the drive shaft and the rest of the suspension.
Also - I like to run with the bottom spring pads sitting as level as possible when the truck is level. But that's just me and my OCD. I want the springs sitting upright, centered, and not as much angle as you have.
Also do any tweaking now before an alignment shop gets it. They check all 4 wheels.
I see Dan has just posted again and yeah, I'd level it up a bit and yes, before any alignment.
Finish your work first, they'll do the alignment after.

 

[ShadowsPapa]

well now it appears to me as though he’s concerned about the driveshaft angle. But the coffee is still soaking in so maybe I’m wrong.

Gee, I've been there before. Don't even have to have a good memory.

The first thing I personally saw was - hey, that rear joint has a fair angle to it.
I guess I zoomed right to that rear drive shaft joint and pretty much ignored the rest of it.
But we all see different things in pictures.......

 

[Rusty PW]

Not in my opinion. They won’t do as well as you do. Control arms are easy to get right because you’re dealing in either full 180 or 360 degree turns and thread counts. Based on what I saw in your picture, I’d shorten the lowers and lengthen the uppers, both by the same amount, and from experience, I’d start with 1/4”.

2X
After looking at the picture again, and blowing it up. I see what he's talking about. I would start with one turn and see what that gives.

The same lift on a different JT will get different results because of tolerances, difference in weight, springs, etc. What Clayton says what the controls arms should be adjusted to is a starting point.

Sponsored