Suspension suggestions (1 Viewer)

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I have a '67 FJ40 that was parked in a barn for 20 years. I have spent 3 years slowly getting it driving and it is finally running. It is pretty much all stock including all original suspension. It has original springs and ORIGINAL SHOCKS! It does have home-made shackles that are about 5 inches center bolt to center bolt, which is about 2' to 2 1/4' longer than stock. I believe this makes about 1" of lift, right? The shackles are about 1/2" longer in the front than the back. It has 33" new mud tires. I like the height of the rig and don't want it very much higher, but one more inch would be ok. I am not really into tall off-road vehicles. I am a field biologist and a hunter and what i use it for is driving offroad on large ranches, mostly through grass pastures, etc. (BUMPY). Driving on hard ground with grass clumps is akin to washboard. With no shocks, my rig is rough riding! I want to improve the suspension and make it the softest, smoothest ride possible. I dont care about flex. I want to be able to drive 15 mps over grass humps and hold a conversation. I have spent days reading threads about 40 suspension and it sounds like the original springs are softer than most or all aftermarket springs. I also read that people say skyjacker softride springs are very soft. I am considering two options:

1) keep original springs and get new shackles (probably greaseable) that are about 6 inches long bolt to bolt.

2) Get skyjacker softride 2.5" lift springs and stock length greaseable shackles.

Can anyone give their best educated guess which will yield the softer ride? Will anyone share their opinions about the two options? Anything else I should be considering buying instead? I don't necessarily have a budget limit, but of course i don't like to waste money.

I am leaning toward fox shocks because they seem like the best for a soft, comfortable ride. Anyone know of a shock that will help make a softer ride?

Here is a photo of my 40. Does it look like about 1" of lift to you?

Another question: I think my timing may be off because it runs hot even though i put in a new radiator (thanks @65swb45 !) and my water pump is pretty new and because at high RMP, it spudders. When I hook up my timing light, there is no visible mark on the flywheel. Is this normal? What is the best way to turn the engine over by hand to look for the mark? My engine is an F built in February 1973. I wish i had a hand crank, but they seem to cost way too much...need to weld one up one day...

One more: My front axle really needs to be rebuilt. I also want to install a locker up front like I have in the rear. Am I wasting my time and money with the ball and claw? Will I regret dumping money into it? Should I buy a newer birfield axle?

Thanks!!!

fj40.jpg
 
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tjhaga

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To help find the timing mark, I would remove all the spark plugs and the distributor cap. Turn the engine over either by remote starter or possibly by pulling on the fan belt, when the rotor points to the area between the 4th and 5th sparkplug look closely thru the window showing the flywheel and you should see the engraved line showing top dead center or the round BB which is 7 degrees BTDC. Paint them with white out or paint and then try your timing light.
 

65swb45

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I usually just pull the inspection cover off the bell housing and pull on the flywheel by hand. That gives me the opportunity to clean the markers when they are at 6’o clock. A lot of folks like to put some sharpie highlighter on them as well while they have the access.
 

kruisinkid

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you can def turn the engine by grabbing the fan belt with gloves on. gets easier with the spark plugs out and you need the first one out any way to find TDC.

i am in the middle of an axle rebuild, which is also now complete steering linkage/end replacement, new front springs and all the shackles/pins/hdw, and of course all new SS and soft brake lines. also painting the front half of the frame.

best of luck with that can of worms in the garage :)
 

DangerNoodle

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I have an OK understanding of leaf geometry. Don't take my word for stuff, please do your research. If I am wrong about something, please let me know. I enjoy learning.

Anyways, here is my advice.

Good shocks with adjustable valving will help with ride quality a lot. you can tune them to give you the best quality of ride, but they don't come cheap. Fox or Bilsteins would probably be your best bet.

Leaf springs aren't known for their ride quality, but they are rugged and easy to use. You can get them pretty comfortable if you play around with stuff, but they will never be coils or independent suspensions, and you can't get them to ride like a modern luxury vehicle. It is a 53-year-old vehicle riding on 53-year-old technology.

The stock springs flex really well. You can also add or remove leaves to stiffen or soften the ride if you go with lift springs. This will affect the height of the lift though. If you want the lifted look, there will be tradeoffs. You could also go about adjusting your shackle length, but there are a few different things you will need to keep in mind with that.

This is the 'optimum' angle for ride, flex, and handling. If you go too extreme with the length/angle of the shackle, it will effect ride, flex, and handling. You can try to perfect the ride, but that will detriment the flex and handling.

leaf-spring-shackle-angle.jpg


You should decide on the look that you want and then go about trying to find the best suspension for you. If you don't care how it looks, going back to the stock geometry with good shocks will probably give you a good ride.
 

DangerNoodle

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Rate is wrong way round in this picture:
View attachment 2272523

I'm not sure if that is correct.

At a greater than 90* angle, the shackle will become part of a link, causing the spring to move upwards before the spring begins to compress. This will give a softer ride until the spring compresses. I'm not sure if I'm explaining it right, but here are a few links for you to look at and read.

 
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I definitely wouldn't add a locker without at least upgrading to a stock fine spline birfield/axle or a aftermarket chromoly axle kit. Personally I would upgrade the front to disc brake either by putting discs on your existing axle or getting a complete disc front axle assembly used from classifieds on here or Craigslist or something, front and rear disc brake would be better if you plan to drive it a lot.

For suspension I would recommend one of two paths based on your budget. A old man emu complete suspension kit with their shocks would ride pretty nice. If you want to spend more money, call Deaver leaf springs and suspension and have them build you custom leaf packs with the ride characteristics you personally want, then have whatever shock company you prefer build you some shocks according to the ride you want.

For timing get an adjustable timing light and that will allow you to see where the timing is if it's way off. Or you could just go through the process and re seat the distributor completely at TDC.
 
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I definitely wouldn't add a locker without at least upgrading to a stock fine spline birfield/axle or a aftermarket chromoly axle kit. Personally I would upgrade the front to disc brake either by putting discs on your existing axle or getting a complete disc front axle assembly used from classifieds on here or Craigslist or something, front and rear disc brake would be better if you plan to drive it a lot.

For suspension I would recommend one of two paths based on your budget. A old man emu complete suspension kit with their shocks would ride pretty nice. If you want to spend more money, call Deaver leaf springs and suspension and have them build you custom leaf packs with the ride characteristics you personally want, then have whatever shock company you prefer build you some shocks according to the ride you want.

For timing get an adjustable timing light and that will allow you to see where the timing is if it's way off. Or you could just go through the process and re seat the distributor completely at TDC.


I was planning to get OME but several people on this site said OME rides a little stiff. What i understood is that they are good for flex but stiff. I would love the opinion of others with OME.
 

DangerNoodle

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I was planning to get OME but several people on this site said OME rides a little stiff. What i understood is that they are good for flex but stiff. I would love the opinion of others with OME.

One of the cruises I have is a 4" OME lift with Rancho 9000s. It rides HARD. it flexes well, but I'm not sure if it is the shocks or leafs, or both that cause the rough ride, but, it is a rough ride.
 

AussieHJCruza

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I was planning to get OME but several people on this site said OME rides a little stiff. What i understood is that they are good for flex but stiff. I would love the opinion of others with OME.
In these parts old man emu is lower tier suspension, especially the shocks. My suggestion is decent leaves that are long enough, unlike many off the shelf springs, so deaver/atlas/Alcan are probably a good idea, plus good shocks, ie fox, Bilstein etc. I wouldn't be putting emu stuff on something I wanted to ride well.

Secondly, make sure the spring rates are suitable for the weight you carry, too high a spring rate and it will ride like a bucking Bronco
 
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Speaking to the leaf springs. I have 2 40’s a ‘78 with reverse shackle, about a 3” lift and non original springs, I believe it is an old man a fre kit. The other is a ‘76 with original leafs and longer shackles that a PO installed when the leafs sagged. That said the ‘76 has a better ride quality. My plan for the ‘76 is to recurve the OEM springs, put on original length shackles and run stock steelies with 31” MT tires. Hope that helps with your dilemma. I have heard the long shackles disrupt handling and are a poor band aid for sagging leaf springs.
 

DangerNoodle

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Who sells long shackles that are grease-able and fit an older FJ40?

Hangar Pins


Shackle Pins


You can find the shackles just about anywhere. It's the pins you want. Ruff Stuff makes some really good, heavy-duty shackles in varying lengths.

 

kruisinkid

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You dont want longer shackles than designed for a certain spring. They should be matched. Its a poor mans lift, like my truck, that flattens the springs and there cause a very harsh ride as you are limiting how far the spring can flex. I had already had on bilstien 5125 shocks for a few years. I went with stock load OME springs in front because of sale price and free shipping but got all hardware from cruiser outfitters. If i had the money to do the whole thing, i would have gone with redline cruisers package which is pro comp springs with bilstein 5125 shocks. That combo seems to have a good rep around here and i already had the good shocks.

the pro tip i learned is ome shackles are a different length than stock because their springs are a different arc/length. Use shackles designed for the springs you are using
 

4Cruisers

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For turning the engine with the flywheel cover off I use a large flat blade screwdriver or small crowbar on the flywheel teeth, leveraged on the bellhousing.
 
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For turning the engine with the flywheel cover off I use a large flat blade screwdriver or small crowbar on the flywheel teeth, leveraged on the bellhousing.

I tightened my fan belt and was able to easily turn the engine by the fan blades. Disy cap off for safety. The bead was painted white but the timing was so far off, the bead was not even visible in the window. I set the bead right on the pointer and the engine died. I backed it off and found the sweet spot and and it runs much better now. In not sure if it is set advanced or retarded but when the timing light flashes, the bead is lower than the pin. Is it normal for the engine to die when set zero degrees? Indication of problem?
 

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