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Unread 01-16-2011, 12:04 AM   #1
billzcat1
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The Comprehensive BDS/FatBob's 2" Lift Thread

Hello All!

I had some extra Xmas money and decided to go with a lift. I chose the 2" BDS springs from FatBob's Garage and paired the springs with Bilstein 5100 Shocks. While this is a pretty expensive way to go for "just a 2" lift", I am very pleased with the results. I will post everything I know here in one thread in hopes it will answer a lot of questions that we see on a daily basis here in the forum. I didn't photograph EVERY step, so some of the pictures are out of order (showing new parts where I describe removal).

The Springs
I picked up a set of "spring only" BDS lift kits from FatBob's Garage. The link to the product is here.

I chose to do a spring lift over a budget boost for several reasons.
1)The original Upcountry springs had sagged as much as 1-3/8" in front. Adding a budget boost on top of worn parts would only give me 5/8" lift over stock.
2)By nature, any sagging springs have also lost some of their original spring rate, making the truck handle poorly. The BDS springs have a higher spring rate than stock, making the truck handle better, despite having a higher center of gravity.
3)When wheeling, occasionally people report having a spring or spacer fall out while flexing. I tend to wheel with the sway bar disconnected, so this might have been an issue for me.
4)With no spacer inserted, they have greater available travel without binding.
5)They have a no-questions-asked lifetime guarantee.

There are three ways to make a lift spring. You can either keep the rate the same and make the spring longer, you can keep the length the same, but increase the rate, or you can use a combination of these techniques. BDS springs are only marginally longer than stock. In fact, they may be the same length as stock, but since mine had sagged their free length was not correct. The rears are obviously a little longer than stock, have an extra coil in them, and have significantly higher rate.

Front Springs


Rear Springs


I estimated spring rates of the stock springs as well as the BDS springs using diameter, number of coils, and wire diameter. Spring Steel is almost universal in composition (for automotive applications), so we can compare them directly. These are estimates based on wire diameter, number of active coils, and diameter of the spring.

Stock Front: 161 lbs/inch
BDS Front: 264 lbs/inch (64% stiffer)
Stock Rear: 217 lbs/inch
BDS Rear: 297 lbs/inch (37% stiffer)

[edit] BDS has commented on this thread that both front and rear springs are actually 240 lbs/inch. I am leaving my estimates up there because the comparison vs. stock is still accurate (the same error was made on both calculations so the percentage will still be VERY close).

Spring Isolators
This section is a new addition. My lift wasn't quite as high as I wanted and I had inconsistent lift height all around. After seeing what new isolators looked like, I was certain that mine had really collapsed. The results are perfect. The conclusion I can make: collapsed spring isolators another real source of WJ sagging. Upper isolators are not as much the problem. My uppers were distorted but not totally junk. The lowers were really quite collapsed.

Here's the part numbers you need:

Upper Front: Mopar: 52088 257AB, Moog: K160040, Raybestos Professional: 5771-704
Lower Front: Mopar: 5208 8401, Moog: K160041, Raybestos Professional: 5771-705
Upper Rear: Mopar: 5208 8346, Moog: K160061, Raybestos Professional: 5771-716
Lower Rear: Mopar: 52088 402AB, Moog: K160042, Raybestos Professional: 5771-706

Here are some pics illustrating the collapsed old isolators and the new ones. I didn't post the upper pics because I am limited to 20 pics per post. They are on Page 3.

Lower Front


Lower Rear


I went with the Raybestos Professional line over the Moog due to warranty, price, pictures, and reputation. The total cost for spring isolators was right around $100 for all 8 from RockAuto If you are looking to save some coin, just get the lower ones. They are the most important and were far more deformed. I REALLY recommend it so you don't have to do this job twice.

As a side benefit, the level of road noise is also greatly reduced and pothole impacts are much softer. Again, I really recommend replacing these, even if you are just getting a budget boost. You will see better results from any lift or even no lift at all - this will put you back to stock height.

The Shocks
I got Bilstein 5100s from Kolak here on the forum. He gave me a price that could not be beat as well as a free shipping promotional offer. This beat out Summit Racing by about $40, which is pretty significant. In addition, I got to support a great forum vendor!

Bilstein's 5100-series are high-pressure-gas-charged monotube shocks specifically valved for lifted applications. More info to be found here. I have used their Sport and HD-series shocks in the past and have always been happy. In addition, they have a lifetime guarantee "as long as it has not been used off-road".

If you purchase Bilstein shocks, you will need to provide some additional hardware. The OEM front shocks have studs welded into the bar pins where the mount to the axle. The Bilsteins just have holes. I tried to remove the studs but it was apparent after several heavy hammer blows that they were not pressed in (like I thought) but actually tacked in place.

Stock


Bilstein


The hardware you will need is 4 5/16-18 x 1-1/4" bolts Grade 5, 8 small 5/16" washers (grade 8), and 4 5/16" Grade 8 nylock nuts. All of these were available from Lowe's. I used Grade 5 bolts because the Grade 8 were not available in the right length, and honestly they will not be under that much strain anyway. The Bilstein shocks come with the appropriate bushings and hardware for the body-mount side, so no worries there.

The Install
The BDS Springs came with a 1-page instruction sheet which I glanced over for pointers, then I dove right in.

Front Axle

1)Loosen Lug Nuts. I discovered that the tire shop put them on "OMG TIGHT".

2)Pop hood and loosen top shock nuts. This is much easier when the rig is still on the ground. One the driver's side, there is a vent hose on a little plastic clip which attaches to the top of the shock. It is stubborn. The vent hose disconnects easily and then the plastic clip can be threaded off.

The offender


Removed


The nut on top is a 15mm and you will need a deep socket to remove it. I put a few drops of MultiOil (my new favorite penetrant) and zapped it off with a 12" extension and an 18v Impact Driver (not an Impact Wrench). This is my favorite tool and many suspension jobs would have been much harder without it. The passenger side is easily accessed. Use the same socket and extension. Pull up the small rubber bushing and washer from the top of the shock.

Passenger Side


3)Jack up vehicle. Be sure to jack in a location that allows you access to the frame rails because you will need to put jack stands there to support the body. Go as high as you can. I recommend at least a 3-ton set of jackstands, although I use a 4-ton usually.

4)Remove wheels/tires from vehicle. With the shocks already disconnected, the axle can droop MUCH more than normal. You may have to jack the body as high as possible, then support the axle with a jack to remove the wheels.

At this point your axle will look like this


Note that the shock is dangling and the spring has already unseated itself from the upper seat.

5)Remove shocks from the vehicle. This is just 2 13mm nuts on the bottom of the axle. Impact driver takes em off in a hurry. The shock lifts right out with no real drama. Throw directly in garbage.

Shocks removed


6)Remove sway bar end links. This will allow more axle droop. The BDS instructions said to also remove the track bar. I did not find this necessary. It's a lot more work and you shouldn't have to do it. The bolt is a 15mm head and the nut is an 18mm head. Due to torsion on the bar, there may be some load on the bolts. You might need to drive them out from the backside or jack a little on the axle to release the preload. You don't need to completely remove the end links, just unbolt from the axle. This gives you more travel if you need it.

7)With your dominant hand, grab the top of the spring and push down/pull out. It is loose enough at this point it pretty much just pops out. If you don't have enough room, then push down on the axle with your foot and you'll gain several inches of clearance.

7a)If you choose to replace the spring isolators, they just pull right off. They may be kind of crusted on there, so pry them up with a screwdriver or something and then clean off the mount. As mine is a West-Coast car, there is not much rust to speak of. For you East-Coasters, I'm sorry but you will probably have LOTS of rust here and you'll at least want to get out a wire brush and some Hammerite/Rustoleum to encapsulate and neutralize the rust.

Spring seat with spring isolators removed


7b)Install spring isolators with tab going into hole on spring seat. The bottoms have a tab on both front and rear axles, but the tops just pop into place.



8)Installing the new springs comes next. They are much stiffer though and a little harder to get in. Make sure the end of the spring lines up with the stop-tab in the rubber isolator at the bottom. Step on the axle again as you push down on the spring and push it in there. I'm only "average" strength and got it in there without much trouble.

Springs installed


9)Install end links. Again, may need to do some jacking to get the axle in the right position. Torque spec is "pretty darn tight". I would say around 70 ft-lbs would be good. I'm not big on torque specs except for critical areas (wheels, bearings, engine internals, crank pulley nut).

10)Install shocks. On top, place one of the included "cup" washers facing up as well as one rubber bushing. Slip this into the open hole in the body and drop the base into the receptacle in the axle. Then, use the new hardware you just bought to bolt it all together. It goes "Bolt, washer, bar pin, axle, washer, lock nut". Torque spec is 21 ft-lbs.

Shock installed


Bottom of hardware (a little fuzzy)


11)Look over everything you have touched to make sure it is tightened.

12)Put wheels back on. This required me to jack up the axle so I could fit the wheels on.

13)Put the truck on the ground.

14)Go back into the engine bay and finish off the shocks. Place one rubber bushing face down, one cup washer face down, and the new locknut. The Bilstein locknuts were 17mm (again, you need a deep socket). I rattled it down with the impact driver, but the correct torque spec is 26 ft-lbs if you care. Re-attach hose and plastic clip on top of driver's side shock.

15)Don't forget to torque your wheel nuts to 100 ft-lbs.

Rear Axle

Unfortunately, I was getting hungry so I wanted to wrap up quickly so I didn't stop to take pictures much for the rear. My apologies. It is easier than the front axle, so once you've done that, the rear is easy.

1)Loosen lug nuts.

2)Jack rear end up. Again, you will need the frame rails for your jackstands, so jack in an area where you keep access. If you have the skid plate back there, I've successfully jacked from it with no drama. If you have the "brush guard" I wouldn't recommend it.

3)Remove wheels.

4)Support axle with jack.

5)Remove shocks from vehicle - both top and bottom bolts take a 15mm socket. The axle will want to droop a lot at this point which is why you have a jack under there.

6)Remove rear sway bar end links - this will make the axle want to droop even more.

Ready to droop. In this pic, I hadn't removed the shock yet.


7)Lower axle with jack.

8)Pull out springs in the same manner as the front. If you need more clearance, you can step on the axle or jack up the OPPOSITE side of the axle (your side will droop even more).

Springs out


9)Remove bump stops from receptacle. They should just wiggle out. You can also use a pry bar or big screwdriver to pry them out. Clean up the dirt on the bump stop and in the receptacle. It will be much easier to re-install.

10)Put some grease around the lip of the receptacle for said bump stop.

11)Inserting the rear springs is a little tougher than the front, but still not that bad. First, jack up the opposite side of the axle to give you max droop. Slip the bump stop up inside the spring. Insert the top end of the spring over the retainer. Align the bottom of the spring to line up with the stop in the lower spring isolator. Then you'll need to wiggle that bump stop back into its home in the axle. I used a big screwdriver to pry it into place.

12)Jack up the whole axle again and install shocks. Top bolt torque spec is 80 ft-lbs, bottom is 85 ft-lbs.

13)Reattach sway bar end links. You'll need to jack up on the axle and maybe jack one side a little to set the preload and actually fit the bolt through the hole. Torque spec same as the front. "Pretty darn tight". 70-75 ft-lbs.

14)Reattach wheels.

15)Put truck back on the ground

16)Torque lug nuts to 100 ft-lbs.

The Results

The overall install only took me 3 hours start-to-finish including a trip to Lowe's to get the shock bolts and stopping to take these pictures for you. If better prepared, I could do it in 2 hours. I would say it is a pretty easy job, maybe 4 on a scale of 10 with wiper blades a 1, radiator replacement a 5, and rebuild of engine a 10.

The ride is firmer than stock, but not harsh or bumpy. Body motion is well-controlled by the Bilstein shocks. The overall stance is much more aggressive. The handling and steering response is greatly improved. As it has only been installed a few hours, I can't comment on off-road behavior, but I have a trip planned for Feb 5th to try it out off road.

The steering wheel was only off-center by maybe 5 to the left. I test drove it and it was barely noticeable. Nonetheless, I fixed it. Loosen 2 15mm nuts on the drag link, shorten drag link 1/4 turn, then re-tighten nuts. Problem solved.

Measurements
Front Fender-to-hub Before: 17-3/8"
Front Fender-to-hub After: 19-3/8" (net lift 2")
Rear Fender-to-hub Before: 18-1/4"
Rear Fender-to-hub After: 20-1/4" (net lift 2")

[edit]After New Spring Isolators Installed
Front Fender-to-hub After: 20" (net lift from isolators 5/8")
Rear Fender-to-hub After: 21" (net lift from isolators 3/4")

[edit]Added 3/4" spacers to the front springs to level it out
Front Fender-to Hub After: 20-3/4"
Rear Fender-to-Hub After: 21"

Measurements were taken with vehicle empty, one car seat in back, one 40-lb tray of recovery gear in hatch area. Fuel tank 1/4 full.

I was surprised that I didn't get more than 2" lift from it based on my sagged springs. At 17-3/8" Fender-to-hub, I had assumed that it was the spring that had sagged over time. Revelation: It may be that the spring isolators are the real culprit for typical WJ sagging. I plan on replacing the spring isolators as well as adding a 3/4" spacer to the front to level the vehicle. See newly-added "Spring Isolators" section for more info.

[edit] I recently read over my build sheet and found that I did in fact have Upcountry suspension on my Overland, so I was sagging from both springs and spring isolators. The total amount of sag from worn-out parts was 1-3/8".

Pictures

Before


After


With 3/4" spacers added up front.



Last edited by billzcat1; 01-16-2011 at 05:35 PM.. Reason: Added pictures
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Unread 01-16-2011, 04:10 AM   #2
outlaw30
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comprehensive and well done. Thanks. I just bought the same shocks from Kolak, and this is timely info to pick up the hardware first! I already have a BB, but even AFTER the BB, my front is only at 18.5" (so, I've sagged 1.5" in the front!!). So, bought new front springs too. Did you extend your bumpstops?
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Unread 01-16-2011, 05:44 AM   #3
billzcat1
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I did not extend the bump stops. I am still running a 245/65-17 so all I have done is increase tire clearance over. In the future, should I step up to a 31" tire I will consider it, especially if I have any rubbing/contact while flexed.
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Unread 01-16-2011, 06:42 AM   #4
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Do you think 3" springs would go in as easily without removing the track bar or using a coil compressor?
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Unread 01-16-2011, 07:56 AM   #5
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Are those the factory upcountry springs you had before the lift? I'm not sure I like the idea of a spring being that much stiffer than stock. If your calculations are correct, that's a huge difference and will make the jeep ride incredibly stiff compared to stock. 60% stiffer is a drastic change. I want to retain as much of the stock ride characteristics as possible. My XJ is lifted with 5.5'' rubicon express springs and monotube shocks, and I'm about tired of the ride quality. Thats one of the main reasons I bought my Overland. I'm curious what the OME spring rates are.
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Unread 01-16-2011, 08:07 AM   #6
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Nice write up! I have the BDS 2" springs as well and can tell you that was money well spent on the Bilstein's. I've already been through the hydro's that were included in the kit they squeeked like crazy. Currently running Rough Country nitro's which are on the firm side especialy on frost heaves in the asphault. Also unless you are planning on discos in the front swaybar, you might want to consider Zone 2" extended links. I put those in recently with the nitro's and they really seemed to stabilize the Jeep through the turns. Great job!
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Unread 01-16-2011, 10:05 AM   #7
billzcat1
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Angry

FleshEater- the 3" springs should have a very similar install. You may have to jack the axles on the opposite side a little more but not much. Measure their free length and I can compare to stock and you'll get an idea of how much taller the OME coil is. I am sure that much like the BDS springs, most of the "lift" is provided by higher spring rates.

hxcjohnny - a 300 lb spring is still not very stiff. I ran 1000 lb front/700 lb rear coilovers on my S4 and it was quite comfortable due to shock valving and suspension design. My fiancee says the Overland still rides very nice, and my daughter still falls asleep on the way to Costco. Ride quality is affected by many factors such as tire pressure, tire construction/load rating, unsprung weight, type of axle, shocks, control arm angle, spring type (coil vs leaf), chassis stiffness, seat firmness.... It just no longer wallows and rolls like an SUV. It is more akin to a sport sedan ride.

TheBoss - thanks for the tip. I am considering the JKS QDs or simply extending the end links front/rear myself through welding.
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Unread 01-16-2011, 05:36 PM   #8
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Added "after" picture for those following the thread.
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Unread 01-16-2011, 06:23 PM   #9
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The OME HD coils measured 13 1/2" for the front and 17 1/2" for the rear.
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Unread 01-16-2011, 06:37 PM   #10
billzcat1
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How odd. You may want to double check you have the right springs. Here are the free lengths I measured.

Stock front: 15-1/4"
BDS front: 15-3/4"
Stock rear: 12-5/8"
BDS rear: 14-1/2"

Maybe you switched front and rear? It would be odd that the front is shorter than stock while the rear is 5" longer.
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Unread 01-16-2011, 07:34 PM   #11
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I measured again and got 13 3/4" and 16 1/2" on the A coils. The shorter one is the front right? These are not listed as front or rear and have no instructions...they're thicker than my thumb.
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Unread 01-16-2011, 07:50 PM   #12
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Thank you for this thread. I was actually thinking about doing this very same mod with 2" BDS from Fat Bob's and Bilstein's. Now I'm not thinking about it, I'm convinced to do it. I will contact Kolak for a price. This thread will make the install a breeze.
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Unread 01-16-2011, 07:53 PM   #13
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I just noticed your stock measurements from the center of the hub. Mine measures 18" in the front and 18 1/2" in the rear on the stock springs.
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Unread 01-16-2011, 08:35 PM   #14
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The shorter coil is the rear. They are shorter and larger outside diameter with greater wire thickness. And yes, my stock measurement was quite low. I think my rubber isolators are collapsed because I was expecting 20" hub to fender.
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Unread 01-16-2011, 09:09 PM   #15
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Quote:
Originally Posted by billzcat1 View Post
I did not extend the bump stops. I am still running a 245/65-17 so all I have done is increase tire clearance over. In the future, should I step up to a 31" tire I will consider it, especially if I have any rubbing/contact while flexed.

I'm running the exact same size tire. Reason for asking wasn't about the rubbing when flexed, but to manage the suspension travel because of the Bilsteins. The body is apparently 2" longer and without extended bumpstops I'm wondering if the springs will be the limiting factor (no problem), or if its the shocks (broken Bilsteins, ouch).
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