Title: lowering to stock height
gianas - July 9, 2012 02:44 AM (GMT)
How do I make a 1954 3B stock height, given the following circumstances, with the desire to keep it at stock height, not higher, for safety reasons?
3B specifications on the 3Bpage state that the height of a 3B is 66 and-one-quarter inches, measured from the top of the windshield.
Mine was stock and correct when I bought it a month ago.
The springs needed replacing.
I replaced the springs and greasable shackles, allegedly according to spec.
Now the jeep, after driving it for a week, is one (1) and-one-quarter inches taller on the left front and two (2) inches taller on the right front, and three (3) inches taller in the rear, so that it will no longer fit into the garage, which is required for insurance purposes. (There’s a Best Top on it, and it’s the rear bow that hits the garage door, now.)
The shocks are stretched nearly two inches in the front and nearly three inches in the rear from their original positions.
Take leaves off the springs? ... Buy oversized shocks? ... Get a new garage-door? ... I've witnessed more than one fatality in flipped and rolled jeeps. Don't want to go there. Jeeps are already high enough; I have no desire or need to go higher than stock.
gianas - July 10, 2012 04:26 PM (GMT)
After new springs, the jeep is two inches too tall in the front and three inches too tall in the rear. What's the "correct" way to bring the jeep to stock, original height?
oldtime - July 11, 2012 12:03 AM (GMT)
Well I do not know how far below standard your particular jeep was before you installed new leaf springs.
I do not even know what springs you installed.
So I don't know if they are correct height or not.
So what brand are they ?
I do not know what shocks you have.
If your shocks meet the specification standards they will limit the spring droop or spring lift accordingly.
What brand and model # ?
Specify your Jeeps tire size and the overall diameter of the tires as they are.
Also how far from ground to garage door opening ?
The leaf springs may or may not loose some of their arch in .....say 1 years time.
oldtime - July 11, 2012 11:51 PM (GMT)
Realize that a top was optional on all CJ's.
The 66-1/4" specification is from ground level to the top of the windshield.
There are definately some errors to found in the Willys publications.
That particular specification appears to be in error.
It appears we may have stumbled upon another publication error.
I suspect it should specify 69-1/4" OAH and not 66-1/4" OAH.
Can other menbers with stock standard 3B's please verify there windshield OAH ?
I currently drive an original nearly stock standard CJ-3B.
The standard 6.00 x 16" tires are about 28.5" diameter.
My current 3B has 6.50 x 16" tires at about 29.5" diameter.
That adds about 1/2" to the OAH.
It is equipped with original stock springs that have lost a small amount of their arc.
The OAH (windshield height) currently measures 69" OAH.
It has a new Bestop Tigertop.
The center bow height of the top is the highest point and it is 72-3/4" as measured from the floor.
My garage door opens up between 74 and 78".
gianas - July 12, 2012 03:31 AM (GMT)
Oldtime, in answer to your questions:
Benz Spring, in Portland, Oregon, made the springs according to these specs: two (2) W-60s and two (2) W-229s. (I can’t explain those specs because the springs were ordered by someone else, someone who said he knew what was needed. I surely didn’t.)
The thickness of each, individual leaf is thicker than the leaves on the original springs. They “look” stronger and stiffer, even to my untrained eye. When the person who ordered the springs saw the springs he ordered for me (before they were installed), he said I should “take out two leaves on each spring if I wanted a comfortable ride.” The installer of the springs—a licensed mechanic who owns a long-standing, complaint-free business—advised against that recommendation of removing leaves. Each mechanic said the other didn’t know what he was doing.
The 1954 3B came with greasable shackles, which I replaced with the same type and size shackles, matching the old ones I kept.
The shocks appear to be original, “Monroe telescopic hydraulic, 10.75 in dia., double acting,” as listed on the 3B-page, “Jeep CJ-3B Specifications.”
Napa has told me that the proper replacement shocks are gas, not hydraulic, Napa part number #94038. “Napa states, in their literature, that the 94038s are “OEM M416 replacement shocks” for the shocks that came on my year and model jeep. New shocks have not yet been added. Does this Napa #94038 shock sound appropriate to you? Or, are there other shocks I should consider, given my use (repeated in second-to-last paragraph)?
The tires are Wildcat XTs (LT235/75R15 M/S), which have a diameter of 17 and three-quarters inches when on the jeep.
The garage door has been moved to 75 inches from the ground, giving two inches of clearance now.
I’m trying to keep this jeep stock and original, everywhere. Higher is not “better” to me, for the following reasons. Only ten-to-twenty-percent of the jeep’s use will be off road, with zero rock climbing. The jeep is my daily driver, where too much height above the intended/originally-engineered height "feels" undesirable and more unsafe, in my opinion, and in the opinion of the licensed auto mechanic who installed the springs, someone who grew up rebuilding and driving jeeps and whose daily driver is a Hummer. He's the one who told me the jeep is now, dangerously too high. What do I know?
In short, every “professional” I consult and hire gives me contradictory information regarding every question I ask, whether about oil or how high this jeep should sit for my use. This is why your input is valued: (1) You haven’t shown that you blow smoke. (2) You haven't been flippant, disrespectful, arrogant, or shallow. (3) You have shown that you have a scientific, experienced-based mind unclouded by rampant greed for material gain. If you knew how lucky some of us feel that you’re around, you wouldn’t be able to get your head into the door of any of your jeeps. Yes, I know someone will tell me to go buy a new jeep or take an auto mechanics class. Not everyone on this forum can be what it would be convenient to be.
Duffer - July 12, 2012 01:44 PM (GMT)
dangerously too high?
The top of my 3B windshield frame sits exactly 72" above the floor. It is actually one of the most stable narrow width Jeeps I have ever driven. What is too high is going to depend on spring rates, shocks, wheel widths and backspacing, tires, how tight the suspension is, frame flex, steering geometry and tightness, and maybe most important, the driver. Even at 72", 75 mph is not in any way uncomfortable in my 3B and I have been driving it that way for nearly 40 years now.
If most use is on-road, the stiffer springs will limit body roll which should increase rollover resistance, as will some good gas shocks. The Rancho RS9000's work very well with the ability to simply adjust the dampening-soft off-road, stiffer on-road.
Bottom line is that there are many factors involved in rollover stability and just lowering the spring height will not necessarily make it safer.
oldtime - July 12, 2012 03:16 PM (GMT)
Previous post edited / please read.....
Can other members with stock standard 3B's please verify the OAH specification ?
Thanks for your kind words.
In truth there are plenty from the past who have not appreciated my position as moderator.
And that's fine with me. To each his own.
I post here because posative commumication is vital to the progress of mankinds social aspirations.
I suggest we strive to keep commumications impersonal.
An impersonal reference for communication is the function of our designated topic... the Jeep model CJ-3B.
Removing leaves can yeild both posative and negative results.
Individual leaves are normally cut to certain lengths and become progressively shorter toward the bottom of the spring pack.
Optimally the individual leaf lengths should be precision calculated.
This incremental decrease of length should be uniform.
Removing leafs should not dramatically effect the overall vehicle height.
Removing leafs reduces the load carrying capacity.
Removing leafs will allow more body lean when driving around curves.
|Bottom line is that there are many factors involved in rollover stability and just lowering the spring height will not necessarily make it safer. |
For standard shock replacement I suggest you install Monroe Gas matic #59017.
Greg, can you lay a straight edge on top of your center bow and provide an OAH ?
gianas - July 12, 2012 05:17 PM (GMT)
Duffer: Thank you for your reply. Forty years experience driving a 3B is good enough for me.
I've been told that I'm on my last legs and will be Willing the jeep to one of my daughters. That is the chief, primary, driving reason why I'm trying to make this a well-maintained, reliable, and "safe" jeep. One of the great values of this forum is that—in most cases—the people who respond are not trying to sell me something, whether products or services.
Oldtime: I will try not to compliment anyone again; (I said, "try"). I understand keeping it impersonal.
Glad I can leave the springs, as made, on the jeep; they are a step above what's sold on the internet, or so they appear to me, and they weren't cheap. So keeping them on the jeep, without modification, feels good to me. (Regarding "without modification": The springs were not correct, as ordered, for my jeep. I had to take them back to Benz Spring, down on Portland, to have them drilled to fit greasable shackles. Now they're $1,000 springs, and I'm not proud but ashamed that fact. I doubt if anyone else on this forum would make that mistake. It's like doctors: If you want competent care, you have to study the topic before you trust someone who claims they know what they're doing. Otherwise, you'll get unexpected, harmful care.)
I'll go look at Rancho and Monroe shocks and get you the top-of-the-bow measurement you requested.
Lawrence - July 12, 2012 09:05 PM (GMT)
Tire size NDT 700X15 Specialty Tire
Ground level to top of windshield is 68 ½”
Ground level to top of tub at tailgate 32 ½”
Ground to highest point of, 1985 vintage Model #51004, Bestop 71 ½”
Ground to highest point of Bestop at tailgate 69”
Duffer - July 12, 2012 10:01 PM (GMT)
|QUOTE (gianas @ Jul 12 2012, 12:17 PM)|
| Oldtime: I will try not to compliment anyone again; (I said, "try"). I understand keeping it impersonal. |
Yeh, no compliments-just maybe Kenipedia. Only person I know that comes close to Ken is a highschool classmate of mine who worked part time at the local Chevy dealer (during both HS and college). Never had to look a GM part number up twice-all in his head. And a lonnnnng time before computers.
No compliments but thanks anyway Ken!
oldtime - July 12, 2012 11:23 PM (GMT)
|Tire size NDT 700X15 Specialty Tire|
Ground level to top of windshield is 68 ½”
Lawrence those figures look about right to me considering your Jeep springs are about 46 years old.
That reinforces my belief that the OAH specification should be 69-1/4" from floor to top of the windshield and not 66-1/4".
As you know tire diameters can easily vary an inch from one manufacturer to another.
What's the actual diameter of your STA 7.00 x 15" tires ?
When I measured my 3B OAH at windshield I placed a straight lightweight board over the windshield arch.
I measured each side while adjusting the board until both sides matched.
That procedure gave me a true height measurement from the center of the windshield arch to the floor.
Can someone else help us verify the correct OAH measurement ?
O. K. Lawrence I see that STA lists your tire as 29.50 diameter.
So if the correct OAH is 69-1/2" it implies that your particular springs sag about 1-1/4" from original.
Those figures appear normal to me.
Lawrence - July 13, 2012 03:28 AM (GMT)
|Lawrence those figures look about right to me considering your Jeep springs are about 46 years old.|
2012 minus 1955 =57
57 year old springs. I guess they are a little weary about now. LOL
gianas - July 13, 2012 03:14 PM (GMT)
Oldtime, you asked me to measure the highest bow on my Best softtop to the ground, as I understand it. Using a level extended from the top bow, my jeep is 74 inches "high."
oldtime - July 13, 2012 03:32 PM (GMT)
74" OAH sounds about right considering you have a new set of springs.
I suppose you have a late model Bestop Tigertop ?
They seem to be a tad taller than the earlier Bestop; like Lawrence has.
gianas - July 14, 2012 01:56 AM (GMT)
Oldtime: I cannot be accurate regarding the precise age of the Best Top, except for knowing that it's been on the jeep so long (before I bought the jeep a month ago) that the color of paint underneath what the top has covered is drastically darker than the quite-faded, original paint that has not been covered by the top. This suggests, to me, that the top is at least ten years old, if not much older. I have no idea how long Best Top has been in business, but this is an old top, certainly not anything that could be called new or "newish."
If I can figure out how to post photos (I'm not that swift with computers), I'll send photos of how much the springs moved the positions of the shocks, both front and rear. I took your suggestion and bought the Monroe shocks you mentioned and plan on putting them on in a few days. Thanks again,
oldtime - July 14, 2012 02:54 PM (GMT)
I hope that Monroe suggestion works out.
I'm not fully sure yet how your leaf springs may have effected the OAH.
Measure jeep OAH at the windshield and not at the center bow because various tops can and do have different dimensions.
I can then get a much better idea of how the springs may or may not have effected the standard lift.
As stated previously I recommend those shocks for use with standard suspension.
They will fit all 80" wheelbased Jeeps CJ2A, CJ-3A, and CJ-3B's at both front and rear. Also CJ-5, CJ-6 at front only.
They are not intended for lifted jeeps. But I suspect you'll be O.K.
Please verify your jeeps OAH from the top of the windshield frame to ground level.
Better yet measure the jeeps OAH with the shocks removed.
There is only one correct way to determine which shock absorber is required for a jeep with modified suspension.
This is done by measuring the shock absorber mounting points between full axle rise and full axle droop.
At full axle rise the leafspring arc flattens out, the axle should hit the axle bumper and the shackles may be getting near horizontal. (never horizontal or past horizontal)
At full axle droop the axle hangs from its own weight and the tire is not in contact with the ground.
Measure the droop / rise with all shocks removed. Measure from top mount to bottom mount.
These axle droop and rise measurements should be taken at both front and rear of the vehicle.
The chosen shock absorber must perform within the measured droop / rise limits.
Rus Curtis - July 14, 2012 05:06 PM (GMT)
Using this third paragraph is what I would suggest to figuring out what shock will work with your springs. IMHO The OEM shocks will not work with even a modest spring lift.
Look at the images. The reason I come to this conclusion is the shocks will be at or near full extension all the time. Pounding the outer limit due to bouncing over road bumps will wear on the shock and/or mount. A longer shock will fix this problem.
Standard hydraulic shocks (original) don't seem to exist anymore. The only thing I've come across are gas charged replacements. This adds a minor boost and may be a great match to original springs. These new shock numbers can be compared for travel limits.
Here's one site to cross check.http://www.willystech.com/faqs/Breakout/Shocks/shockref.htm
This site has a few additional links (most seem broken) but there are probably a dozen or more additional comparison sites on the web. Like Monroe:http://www.monroe.com/assets/downloads/eng...LengthSheet.pdf
If you aren't going to do hard off-roading (full articulation) or haul a full load of bricks or fire wood, you may never see full compression on your springs (see the Columbian coffee jeeps). Typical road driving or light dirt road exploring will only flex your springs just a little bit. I simply got the dimensions of the standard shock from my SM,
S-9. SHOCK ABSORBER SPECIFICATIONS
(same for front and rear)
I then added a few inches of extension to cover the outer limit of travel (confirmed by lifting frame for wheel drop). The lower limit was close (only lost 1 7/8” compression).