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  #21  
Old 05-27-2020, 04:13 AM
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Brynjminjones Brynjminjones is offline
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Damn, that's the wrong answer, didn't you all get the memo?
You were supposed to say "those look great, they absolutely don't need replacing!!"

Looks like it's time to start pricing up some replacements, although I may still try removing the shocks in case they're also an issue.
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  #22  
Old 05-27-2020, 05:14 AM
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Brynjminjones Brynjminjones is offline
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Okay, so now I'm looking at replacement leaf springs and it feels like I've opened a can of worms!

My GW has 7 leaves on the front, 5 on the rear.

The Jeep parts manual says I need part number J536 2953 for the front, and J536 2956 for the rear.


I went straight to BJ's first. Their imported fronts are 4 leaf. The USA ones are 6.
The imported rears have 3 plus overload, the USA ones are 4 leaf plus overload.

I then looked at RockAuto, which does have some with the same number of leaves. However, I cross-referenced the Dayton 97-400 front leaves, and they are J536 2951 , which is actually the part number for the standard duty front springs in a J10/20, not a GW. It's a different part number so I'm guessing they must actually be different.

I couldn't find a cross reference for the rears at all!


Can somebody point me in the right direction to find direct replacements for what I have currently?

Also, as I'm in the UK, are there specs available anywhere so I could have some made up? I've had a look but not much success.
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  #23  
Old 05-27-2020, 05:17 AM
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J76137 J76137 is offline
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I agree with letank and rang-a-stang. Those springs actually have a negative arch in the front. If you look closely you can see that the front of the top spring is bending over the next lower spring. Judging from the amount of rust on them the whole spring pack is likely sticky and worn.
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  #24  
Old 05-27-2020, 06:10 AM
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Brynjminjones Brynjminjones is offline
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Yes, I think you're right. Here's how the rear of the spring looks, it's even worse.

IMG_20200526_135246 by Brynjaminjones, on Flickr

I'm sure the rear are shot too. This is how much it sags towing a ~1000lb trailer:

IMG_20191004_123140 by Brynjaminjones, on Flickr
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  #25  
Old 05-27-2020, 05:42 PM
wiley-moeracing wiley-moeracing is offline
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you need to order up a new set of springs, front and rear. I would think you could find a local spring shop there that may be able to build you a new set?
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  #26  
Old 05-28-2020, 02:42 AM
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Brynjminjones Brynjminjones is offline
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Thanks, I'm looking into it now to see what I can find!

There's a local shop with a great reputation that should be able to build some for me, but I don't know what specs to give them.

I've also found some Crown springs in the country for a good price. Are stock replacement Crown springs any good?
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  #27  
Old 05-28-2020, 04:29 AM
wiley-moeracing wiley-moeracing is offline
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They will work if you can find them.
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  #28  
Old 05-28-2020, 09:17 AM
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rang-a-stang rang-a-stang is offline
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I had a set on mine and they were a little soft for my liking but sounds like that may be perfect for you!
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  #29  
Old 05-28-2020, 10:25 PM
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DarkMonohue DarkMonohue is offline
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I'm going to splice and rearrange quoted pieces so that we can discuss springs and dampers separately. Let's do springs first.


Quote:
Originally Posted by Brynjminjones
I know the springs are worn, but I'd guess that they'd become softer with time rather than firmer.
I'm not sure whether springs become softer when they sag, or simply lose ride height. Either way, rocklaurence makes an excellent point:

Quote:
Originally Posted by rocklaurence
My guess is that your bottoming out on the bumps due to sagging springs. With good springs you should have 3-4" of space between the axle tube and the bump. If your at 2<" it'll transfer all that energy into the frame.
This is really important. The cushiest springs and shock absorbers in the world will ride like hell if the axles are bouncing off the frame every time you hit a pebble. Did you get a chance to measure that distance between the tops of the axle tubes and the bottoms of their respective bumpstops? It's worth a look so that you can better understand what your problems really are before you start changing things.


Quote:
Originally Posted by Brynjminjones
I'm sure the rear are shot too. This is how much it sags towing a ~1000lb trailer...
Unless you have the car loaded up with a whole lot of heavy cargo, or the trailer tongue weight is far in excess of 150 lb (typical tongue weight for a 1000-lb trailer), it should not be sitting that low in the back.


Quote:
Originally Posted by Brynjminjones
There's a local shop with a great reputation that should be able to build some for me, but I don't know what specs to give them.

I've also found some Crown springs in the country for a good price. Are stock replacement Crown springs any good?
For my money, I'd take the Jeep to the local spring shop and let them look it over in person. I'd bet that they can get all the information they need just by looking at your springs. Odds are good a trained, experienced eye will see right away where the leaves have changed shape and what sort of arch they originally had.

Besides that, if you do have a problem with local work, you can walk in and make yourself a pest until you reach a resolution. It would be a lot harder to do that if you aren't happy with the Crown springs, especially if any time has passed. You can do a quick search here to learn of Crown's reputation. It ain't universally positive.


Quote:
Originally Posted by Brynjminjones
Are these Monroe Gas-Magnums known to be firm shocks, and would changing them likely sort my problem?
Ride quality is subjective, and shocks are only one part of the system, but Monroe's shocks seem to have a general reputation for being softer than comparable products from other manufacturers. That said, anything labeled "heavy duty" may be stiffer than you want if ride quality is a priority. I put Gabriel Max Control shocks on my J20 and wish I'd gone with something less robust. Even for a pickup configured for fairly heavy loads, it's extremely harsh unless very heavily loaded (e.g. a thousand pounds or more).


Quote:
Originally Posted by Brynjminjones
I took it down some dirt roads to test and it actually rides pretty nicely on the bigger bumps, it's just smaller imperfections on the road where it seems unnecessarily harsh.
That does seem to point toward shock absorber damping that allows the suspension to respond to bigger/harsher impacts, but not smaller ones. At the risk of oversimplifying a fairly sophisticated science, your shocks probably have more damping than is appropriate for your vehicle and its usage.

Sorry, but it sounds like you're probably in need of new springs to correct the sag and restore full suspension travel as well as more appropriate shocks to get the ride comfort back.
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  #30  
Old 05-30-2020, 10:57 AM
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Brynjminjones Brynjminjones is offline
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DarkMonohue, thank you for that incredibly helpful answer!

I will read through and answer properly when I've got a bit more time this next couple of days
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  #31  
Old 05-30-2020, 08:49 PM
Theodore Theodore is offline
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Hey, Brynjminjones, now that you are in the market for springs & shocks, I would recommend US-made Dayton springs from SDTruckSprings; just make sure you specify Dayton US-made. I got 97-400 & 97-485 from there, and 58567 Monroe Load-leveler shocks elsewhere. Our Wagoneer started out with a 3-in lift and terrible ride; I swapped springs and shocks last summer to bring it back to stock.

Can read about the tale here: https://www.fsjnetwork.com/forum/vie...hp?f=7&t=17603.

It took a while to work thru it, but we are happy with where we ended up.
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  #32  
Old 05-31-2020, 08:49 AM
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Kaiserjeeps Kaiserjeeps is offline
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If the new springs have clamps that facilitate separating them, buy some slip plate #1 and paint each leaf contact surface. Being a dry graphite lubricant it won't attract dirt, it gets better with use and will polish and create an amazing ride.
And you never have to look at it again. This solution is not well known apparently. But it works better than anything I have seen or read about yet.
Fisherman from the M715 zone deserves the credit for this. I can say his extremely stiff military truck rode like a Cadillac after putting slip plate on. I am doing it to mine. I also put it on a lot of metal to metal moving parts on my last restoration. Window lift mechanisms etc. It is greats stuff and works.

https://www.slipplate.com/
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  #33  
Old 05-31-2020, 08:18 PM
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That slip plate stuff sounds awesome, I'd still ante up for some shocks first.. Bilsteins are on all my Jeeps.
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  #34  
Old 06-01-2020, 09:19 AM
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Brynjminjones Brynjminjones is offline
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Thanks all for the help.

We've been out in the Jeep some more this weekend and paying attention to how it rides.

I really don't think it's hitting the bump stops. It's actually better over big bumps than little ones, although it always feels too stiff to hit the bump stops.
Our F100 hits the bump stops frequently and I'm very used to how that feels!


I'm in touch with a local spring place, although looks like they need chasing up.
I'm also considering the Crown springs, but I'm aware of Crown's reputation and have had my own bad experiences with their other products in the past.

Theodore, those springs you have are the exact same ones I've seen on RockAuto. If it weren't for the shipping cost to the UK, I'd have been very interested in them.
How does yours ride now?

That Slip Plate stuff also sounds worthwhile. I'll do some proper reading into it once I eventually settle on which springs to buy.


I did get a little carried away after a couple of beers the other night and now have some new shocks on the way.
I went for KYB Excel-G shocks in the end, as they are supposed to be OEM replacement and I've heard several people say they ride softly.
We'll see if they make a difference in a week or so when they get here.
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  #35  
Old 06-02-2020, 04:57 PM
Theodore Theodore is offline
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Quote:
Originally Posted by Brynjminjones
Thanks all for the help.

Theodore, those springs you have are the exact same ones I've seen on RockAuto. If it weren't for the shipping cost to the UK, I'd have been very interested in them.
How does yours ride now?
.

Love the ride and the stance now. Especially after adding the 1/2-in block on rear drivers side to level it up. Much better than before.
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  #36  
Old 06-02-2020, 09:54 PM
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Heavy_Metal_Thunder_81 Heavy_Metal_Thunder_81 is offline
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I'd go with the BJ's stock springs. They're made by a very reputable spring manufacturer in California that is famous for building the springs on desert race trucks. BJ's also ships internationally.
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  #37  
Old 06-06-2020, 02:56 AM
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Brynjminjones Brynjminjones is offline
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Thanks both above for the advice on the springs. I'd love to buy from BJs, but unfortunately the shipping is just so expensive.
I'll see if I can maybe find a way to get them over cheaper, like possibly in a container that's already coming over.


In the meantime, my new shocks have arrived and I've got them installed. A much easier job than I had expected!

After taking the old shocks off, it's apparent that the front passenger side was definitely done for!
The other three all fully extended when removed, but this one just stays wherever it's set. It also seems to have way, way more rebound resistance than the others.

By comparison (to the three functional shocks), my new ones seem to need just as much force to compress, but easier to extend.

I've only been for a very short drive, but so far the ride seems to have lost its harshness and be a good bit more comfortable.

I'll report back when I've been for a decent drive though!

IMG_20200605_141519 by Brynjaminjones, on Flickr
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