Coil over - 1953 M38A1

p38

Caught the Bug
IMG_2879.jpg

My 1953 M38A1 has been back on the road for a couple of years and we've decided it's time for some upgrades.

The 5 lug Dana44/60s will be replaced by 8 lug 60/60. The Allied bead locks will be replaced by Hutchinsons, and I might go with a bit larger tire. If we have time before Moab, the leaf springs will be replaced by coils overs. The old SM420 is coming out, and an NOS Con-diesel 420 is going in. I hope the coils will fit without having to build a new fuel tank or too much modification of the frame, that would be the biggest delay.

I have only heard positive comments about switching to coil over, anyone have a bad experience?
 

cozdude

Guy with a Red 2-Door
I can't comment on switching from leafs to coilovers and what it takes for the conversion but all I can say is that's a bad ass rig!!
 

p38

Caught the Bug
Thanks guys. I hope all the results are positive. I hate to mess up a good thing. Sort of the - "If it ain't broke don't fix it" rule, but the 8 lug 60s will give me bigger brakes and the coils will allow more articulation. I won't throw any of the parts away just in case.
 

wayoflife

Administrator
Staff member
I have only heard positive comments about switching to coil over, anyone have a bad experience?

If you're just going to trailer your Jeep everywhere, you should be fine with coil overs. The problem with coil overs or at least, back in the day was that none of them were dialed in for DD use and were kind of sketchy to drive on pavement. That all changed with the JK and with companies like EVO designing kits that had spring rates and valving that worked well across the board. Getting a custom setup to work well in all conditions might be a challenge but I'm sure it can be done.
 

p38

Caught the Bug
If you're just going to trailer your Jeep everywhere, you should be fine with coil overs. The problem with coil overs or at least, back in the day was that none of them were dialed in for DD use and were kind of sketchy to drive on pavement. That all changed with the JK and with companies like EVO designing kits that had spring rates and valving that worked well across the board. Getting a custom setup to work well in all conditions might be a challenge but I'm sure it can be done.

Thanks - that is my main concern, and was the reason I didn't go to coil over when we rebuilt it 2 years ago. The guy who built what you see now is doing the conversion, he has had great results with the coil overs he has done. He did explain the narrowness of my frame compared to newer jeeps could be an issue. We might end up with leafs in the back, but we will give it a try.

My daily driving isn't very far - hopefully won't be an issue.
 

ScoobyCarolanNC

Active Member
Please take tons of pics & keep posting! We need more classics around here. I love that you've got the tent top, no pavement princess here.


Sent from my duck blind.
 

professorkx

New member
I converted my son's 1978 CJ5 to 3 link front and 4 link rear last year with good results. I moved the front axle forward 4 inches and the rear axle back 6 inches for a better wheelbase, and 70mph on the highway is very stable. The only issue we have not addressed is that the Kings valving is way too stiff. My son lives 14 hours away, so I only have pictures of the build...he still needs to send me action shots. In addition, the jeep is driven the 14 hours to/from my shop, so very road worthy.









This next picture shows the track bar mounted behind the axle, which was necessary because the frame mount would not clear the drag link on extreme articulation if we mounted it in the front. (be prepared to articulate each axle about 50 times, as you will want to constantly check clearances during your build) We noodled this for a while before we mocked it up, as I was concerned the track bar would hit the third link. There wasn't any contact in articulation, but there wasn't much wiggle room either. The solution was to french the track bar about 1/4" at the potential contact point, so there is now plenty of room in all articulation configurations.





we built both axle bridges from scratch, which required a very slow welding process to ensure I didn't warp the housing.





The one wrinkle I didn't expect was with the exhaust. The headers were just below the bottom of the frame, which worked fine on the drivers side. However, on the passengers side, with two links, the header had to be shortened so it was above the top of the frame rail.

Here is the header prior to modification



Header after I shortened, but before it was cleaned up and painted.



Fitting the rest of the exhaust inside the frame rails with the 4 links in the rear required some pretty creative fabrication, but in the end, it works well and exits the jeep just below the frame rails in the rear.

This conversion took 3 months of nights and weekends. After driving, I would do another conversion. Next time, I want to use coils from a new JK instead of coil over shocks, and use a 3 link in the rear, as I think this will keep me from such heavy frame modifications in the rear. I essentially built a new frame in the rear to allow for the tall shock tower. The rear bumper is now part of the frame to keep everything aligned, and I added 2x3 tubing behind the shock tower that connected the rear bumper to the original frame rail.

Lots and lots of things to figure out in a conversion of this nature, but everything had a solution. We spent a lot of money on welding gas and wire, and over $200 on 4" grinding wheels to give everything a finished look. Quite frankly, it was easier to build my own chopper from scratch than it was to convert to coil over shocks, but it's all fabrication and design, so all fun.

 

p38

Caught the Bug
I converted my son's 1978 CJ5 to 3 link front and 4 link rear last year with good results. I moved the front axle forward 4 inches and the rear axle back 6 inches for a better wheelbase, and 70mph on the highway is very stable. The only issue we have not addressed is that the Kings valving is way too stiff. My son lives 14 hours away, so I only have pictures of the build...he still needs to send me action shots. In addition, the jeep is driven the 14 hours to/from my shop, so very road worthy.









This next picture shows the track bar mounted behind the axle, which was necessary because the frame mount would not clear the drag link on extreme articulation if we mounted it in the front. (be prepared to articulate each axle about 50 times, as you will want to constantly check clearances during your build) We noodled this for a while before we mocked it up, as I was concerned the track bar would hit the third link. There wasn't any contact in articulation, but there wasn't much wiggle room either. The solution was to french the track bar about 1/4" at the potential contact point, so there is now plenty of room in all articulation configurations.





we built both axle bridges from scratch, which required a very slow welding process to ensure I didn't warp the housing.





The one wrinkle I didn't expect was with the exhaust. The headers were just below the bottom of the frame, which worked fine on the drivers side. However, on the passengers side, with two links, the header had to be shortened so it was above the top of the frame rail.

Here is the header prior to modification



Header after I shortened, but before it was cleaned up and painted.



Fitting the rest of the exhaust inside the frame rails with the 4 links in the rear required some pretty creative fabrication, but in the end, it works well and exits the jeep just below the frame rails in the rear.

This conversion took 3 months of nights and weekends. After driving, I would do another conversion. Next time, I want to use coils from a new JK instead of coil over shocks, and use a 3 link in the rear, as I think this will keep me from such heavy frame modifications in the rear. I essentially built a new frame in the rear to allow for the tall shock tower. The rear bumper is now part of the frame to keep everything aligned, and I added 2x3 tubing behind the shock tower that connected the rear bumper to the original frame rail.

Lots and lots of things to figure out in a conversion of this nature, but everything had a solution. We spent a lot of money on welding gas and wire, and over $200 on 4" grinding wheels to give everything a finished look. Quite frankly, it was easier to build my own chopper from scratch than it was to convert to coil over shocks, but it's all fabrication and design, so all fun.




So what is the length of the new wheelbase? The guy doing my conversion just did one on his Bronco; he had valving issues as well but found someone who went through and adjusted them all. He says the ride/cornering is perfect. My frame should be about the same width as your son's CJ - so I hope I get the same good ride. Like you said - it's just gas and wire - we thought about just building a new frame and swapping the body. It would make it easier to swap back if it doesn't turn out. If it does turn out - we throw another body on the frame.

Nice bike.
 

p38

Caught the Bug
Darn, I like those and thought maybe they would be for sale eventually. Where did you purchase yours?


Sent from my iPad using WAYALIFE mobile app

They will be if we don't find another jeep to put them on. I don't know exactly where they were purchased, the guy who built my jeep supplied them. I can ask him.
 

JKbrick

Active Member
They will be if we don't find another jeep to put them on. I don't know exactly where they were purchased, the guy who built my jeep supplied them. I can ask him.

Mine are the stock 5 on 5, thank you though. I actually got a deal on some slabs today from a different thread!


Sent from my iPad using WAYALIFE mobile app
 
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