Axle's before lift or...

Evening all,

It's rather embarrassing to ask questions with such a lack of knowledge so I hope you'll bear with me.

I currently have a 4.5" SA lift on my XJ. I'm definately going to be putting on a LA kit this spring/summer. I'd also like to upgrade my current D35 and possibly my D30 but I was wondering if I need/should upgrade my axles BEFORE doing the lift or can it wait a little longer?

My reason for asking is this; My ride is rough. When I mean rough, I mean ROUGH! I'm not looking for a Cadillac ride here. I do like a "rougher" ride that I get from a truck/Jeep but what I have is pretty ridiculous. So after some researching and advice, I've decided to refresh my Kee a bit and go for a FUll LA kit and shocks (Probably Bilstein 5100 series and IRO) along with an OTK steering kit and DS track bar and definately a SYE kit.

Later on, I plan on using another vehicle as my DD but for now I'm using it as such so I'm not looking to go TOO aggressive but at the same time, I'd like the piece of mind stonger axles and other compnents give. While I have little knowledge of doing many of the things I'd like to do, I'm going to do it myself...maybe with the help of some fellow Jeepers? Maybe I should ask in my chapter forum for that though.

My XJ: 2001 4.0 5 speed, NV3550 transmission, NP231 TC. Any other info that might help?

What size tire are you going to run? I would just keep an eye out for a read D44 or chy 8.25 and swap it in when you find one. I wouldn't delay the lift, if anything it would be easiest to swap in the axle when your doing the lift.

So, I'm going to assume that you want to run 33s? The 30/35 combo is ok when the diffs are open with 33s, but you should try to upgrade the rear axle to something better, a 29 spline 8.25 is a direct swap, Ford 8.8 would need a bit of custom work but nothing crazy. It all depends on what you want to do with it, your budget, your driving style, what you wheel on/in.

whitexj98 said:

What size tire are you going to run? I would just keep an eye out for a read D44 or chy 8.25 and swap it in when you find one. I wouldn't delay the lift, if anything it would be easiest to swap in the axle when your doing the lift.

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Ahh! Sorry...forgot to add tire size.

Currently, I'm running 285/70/16 but I'd like to go to 305/70/16 (basically a 33/12.50)

XJskibum said:

So, I'm going to assume that you want to run 33s? The 30/35 combo is ok when the diffs are open with 33s, but you should try to upgrade the rear axle to something better, a 29 spline 8.25 is a direct swap, Ford 8.8 would need a bit of custom work but nothing crazy. It all depends on what you want to do with it, your budget, your driving style, what you wheel on/in.

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Yes sir. I'd like to run a 33/12.50 (Or close to it). When you say open diffs, I'm assuming you mean not locked? Pardon the dumb question...

Thanks for any and all replies by the way. I'm really trying to learn and do things myself instead of taking it to a shop.

Your '01 probably has a low pinion D30 up front. I would look for a HP D30 and either a 29 spline 8.25 or an XJ D44. These axles can be beefed up fairly cheaply so your overall investment is much smaller than buying name brand axles.

jeeperjohn said:

Your '01 probably has a low pinion D30 up front. I would look for a HP D30 and either a 29 spline 8.25 or an XJ D44. These axles can be beefed up fairly cheaply so your overall investment is much smaller than buying name brand axles.

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If its stock, it Definately has a LP D30,and since he's got a D35 he also has ABS to deal with!

Gaidge said:

Evening all,

It's rather embarrassing to ask questions with such a lack of knowledge so I hope you'll bear with me.

I currently have a 4.5" SA lift on my XJ. I'm definately going to be putting on a LA kit this spring/summer. I'd also like to upgrade my current D35 and possibly my D30 but I was wondering if I need/should upgrade my axles BEFORE doing the lift or can it wait a little longer?

My reason for asking is this; My ride is rough. When I mean rough, I mean ROUGH! I'm not looking for a Cadillac ride here. I do like a "rougher" ride that I get from a truck/Jeep but what I have is pretty ridiculous. So after some researching and advice, I've decided to refresh my Kee a bit and go for a FUll LA kit and shocks (Probably Bilstein 5100 series and IRO) along with an OTK steering kit and DS track bar and definately a SYE kit.

Later on, I plan on using another vehicle as my DD but for now I'm using it as such so I'm not looking to go TOO aggressive but at the same time, I'd like the piece of mind stonger axles and other compnents give. While I have little knowledge of doing many of the things I'd like to do, I'm going to do it myself...maybe with the help of some fellow Jeepers? Maybe I should ask in my chapter forum for that though.

My XJ: 2001 4.0 5 speed, NV3550 transmission, NP231 TC. Any other info that might help?

Click to expand...

I'm jealous!

jeeperjohn said:

Your '01 probably has a low pinion D30 up front. I would look for a HP D30 and either a 29 spline 8.25 or an XJ D44. These axles can be beefed up fairly cheaply so your overall investment is much smaller than buying name brand axles.

Click to expand...

Exactly what I'd do.

RCP Phx said:

If its stock, it Definately has a LP D30,and since he's got a D35 he also has ABS to deal with!

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SPOBI - ABS implies a d35, but a d35 does NOT imply ABS.

OP - I would get a high pinion d30 to install while doing the lift, and a 29 spline 8.25 or ford 8.8 (depending on what you're going to gear it to) as well. Since you're swapping out leafs and coils and links already, you are 95% of the way to swapping axles... it is easiest to just put it up on jackstands, rip it all out, install the new stuff and new axles and be done with it.

What axle gear ratio are you thinking of going with? Depends on what size tires you're going with and your personal preference, 3.55s and 32s or so will be close to stock on a 5-speed (and you can find an XJ with 3.55 geared axles in good shape nearly anywhere), but 4.10s will crawl better. If you are aiming for 4.10s, try and find the front axle out of a 95-99 4 cylinder 5 speed XJ in the junkyard. If it's got an 8.25 rear, get that too... else you can pick up a ford 8.8 from a ford explorer 95 or later, find one with 4.10 gears. You'll have to do some welding to put an 8.8 in, but during the lift is the ideal time to do it because you can weld the spring perches at exactly the right angle and avoid having to spend $25-50 on a set of leaf shims.

RCP Phx said:

If its stock, it Definately has a LP D30,and since he's got a D35 he also has ABS to deal with!

Click to expand...

I'm almost positive I don't have ABS. The only reason I say this is (As I've never actually checked nor do I know how at this point) I've never felt the ABS kick on when I hit the brakes in the snow. The tires just lock up and I slide. Maybe not the most reliable test to find out though...

kastein said:

OP - I would get a high pinion d30 to install while doing the lift, and a 29 spline 8.25 or ford 8.8 (depending on what you're going to gear it to) as well. Since you're swapping out leafs and coils and links already, you are 95% of the way to swapping axles... it is easiest to just put it up on jackstands, rip it all out, install the new stuff and new axles and be done with it.

What axle gear ratio are you thinking of going with? Depends on what size tires you're going with and your personal preference, 3.55s and 32s or so will be close to stock on a 5-speed (and you can find an XJ with 3.55 geared axles in good shape nearly anywhere), but 4.10s will crawl better. If you are aiming for 4.10s, try and find the front axle out of a 95-99 4 cylinder 5 speed XJ in the junkyard. If it's got an 8.25 rear, get that too... else you can pick up a ford 8.8 from a ford explorer 95 or later, find one with 4.10 gears. You'll have to do some welding to put an 8.8 in, but during the lift is the ideal time to do it because you can weld the spring perches at exactly the right angle and avoid having to spend $25-50 on a set of leaf shims.

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(Again, I appologize in advance for the lack of knowledge and dumb questions.)

Is a HP D30 that much more durable than a LP D30?

As far as gearing goes, my XJ is still a DD and mostly highway to and from work so as much as I'd like to go into some deeper gearsets, I was looking at no more than 4.10's as anything deeper would crush my wallet. I already fill up almost once a week with 3.07's. and a 45 mile round tripper to work every day.

As far as tires go, I'm currently running 285/70/16 and I'd like to run no more than a 305/70/16.

I'm assuming a C8.25 is a close swap in as opposed to the F8.8? I don't have access to a welder nor someone who knows how to weld so that'd be the toughest part but I'm not opposed to finding someone if you think the 8.8 with a little backspacing would be a better fit than the 8.25.

I have oceans of questions and the more I search, the more it confuses me but I'm more than willing to learn so....that why I'm here asking dumb questions. I'm also trying to get the nerve to do this stuff on my own...it's pretty overwhelming when you've never done something other than changing your own oil, plugs and wires.

OP- I am in a similar situation, so your "dumb questions" are the same that'd I'll end up asking next week. Haha.

I have a RC 4.5 aal kit and I'm looking to get a real leaf pack before I put an axle back under it. I just havent decided on which axle. I'm not planning on running anything over 33's either.

So...Keep firing those questions, they are helping more than you know.

Gaidge said:

I'm almost positive I don't have ABS. The only reason I say this is (As I've never actually checked nor do I know how at this point) I've never felt the ABS kick on when I hit the brakes in the snow. The tires just lock up and I slide. Maybe not the most reliable test to find out though...

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You probably don't then. To make sure, look at the rear brake hose where it goes from the body to the axle. If it has two cables clipped to it, one going to each wheel, you have ABS. If it doesn't, you don't.

Gaidge said:

Is a HP D30 that much more durable than a LP D30?

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It's more durable, and is better when lifted as it keeps pinion angles somewhat better. They are also more common in the junkyard, as they were available for the better part of a decade while the low pinion axle that bolts into the XJ was only in the TJs and 00/01 XJs.

Gaidge said:

As far as gearing goes, my XJ is still a DD and mostly highway to and from work so as much as I'd like to go into some deeper gearsets, I was looking at no more than 4.10's as anything deeper would crush my wallet. I already fill up almost once a week with 3.07's. and a 45 mile round tripper to work every day.

As far as tires go, I'm currently running 285/70/16 and I'd like to run no more than a 305/70/16.

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Well, you basically want to aim for "a little deeper than the gear ratio that would put you back to stock gearing for your tire size." For example, factory auto jeeps usually had 3.55s and 28" tires. Toss 33" tires on one, and it becomes somewhat of a dog... but putting 4.10 geared axles into it, and you're only minorly undergeared. Similarly, "stock" gearing for 285/70r16s (31.7 inches diameter) on a manual XJ would be something like 3.47; putting 3.55 geared axles out of an auto on it will feel almost factory since that's a little overgeared for the change in diameter. The extra gearing just helps you accelerate by overcoming the extra rolling mass the larger tires have. Your gas mileage will probably return to at least close-to-stock with 3.55s but it depends on the vehicle and driver.

Gaidge said:

I'm assuming a C8.25 is a close swap in as opposed to the F8.8? I don't have access to a welder nor someone who knows how to weld so that'd be the toughest part but I'm not opposed to finding someone if you think the 8.8 with a little backspacing would be a better fit than the 8.25.

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a Chrysler 8.25 out of a late model XJ is 100% bolt in - same width, same everything. Buy new U-bolts (different diameter axle tubes) and get a driveshaft from a 5spd 96 or later XJ with the 8.25, bolt it all in, and you are done. The 8.8 is a good deal stronger, it's closer to dana 44 strength (and in some ways surpasses the 44) but most people swap it in because it's cheap, just as plentiful as the 8.25 in the junkyards, and is very frequently found with deeper gears (3.73 is most common, 4.10 is also common) and comes with disc brakes 95 and later. The 8.25 is a great axle, but is most common in 3.07 and 3.55.

In your case since you would be pretty OK on 3.55s with your current tires, I'd just pick up a set of axles out of auto XJs. You can get a good d30 out of a 95 to 99 4.0/AW4 XJ and a good 8.25 out of a 97-01 4.0/AW4 XJ; these are just the best years for the parts you're looking for, wider year ranges will fit.

If you put your mind to it you can learn basically everything about the stock XJ build options and parts year splits pretty quick... I didn't even know what a dana 30 was when I signed up here. I just read a lot and remember part numbers and year splits fairly well.

Oh, and keep your old frontend around if you swap it out. The unit bearings can be used as part of a WJ brakes/steering swap at some point in the future if you decide to do that, and the shafts have the larger u-joints and are good trail spares (all 95-01 XJs had the larger u-joint shafts, and earlier years had them too if ABS was installed.)

Kastein,

Thanks so much for all of the information and especially your patience. It's definately appreciated.

Now, to build up the courage to pull the trigger on buying and installing them...

Thanks all.