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cumminscruiser
01-29-2009, 02:32 PM
Is it worth the time to disassemble the leaf springs and install pads to allow the leafs to move more freely, and are the slip pads available? Would picces of teflon work for this application. What about the brackets?

Alaska Mike
01-29-2009, 05:03 PM
From TeriAnn Wakeman's site (http://www.expeditionlandrover.info/leafSprings.htm):
"Once you have the springs that provide the best dampening for the weight of your vehicle, the next step is to minimize the friction between the individual leaves. I like UHMW (ultra-high molecular weight) Polyethylene plastic.

This plastic provides a low friction surface, similar to Teflon tape, but with a much higher abrasion and puncture resistance. It was designed specifically for commercial use on chutes, packaging lines, slides, and anywhere high pressure metal to metal sliding contact occurs. It also provides sound dampening, eliminating squeaks and rattles caused by adjacent parts movement. The plastic's temperature range is -40 to +225 degrees F.

The plastic tape I like is 0.005" thick, comes on a 3 inch wide roll and has 1.5 mils of acrylic adhesive. It can be purchased from McMaster Carr (http://www.mcmaster.com/) and is part number 76445A24 (You can do a part number search on their site to find the tape).

You disassemble the spring pack and stick the tape to the top side of each individual leaf, except for the top leaf of course. This tape virtually eliminates the friction between adjacent leaves in the leaf pack and dramatically increases the spring's ability to react to bumps in the road."

I did this on my Rover's rear springs, but I haven't tested them yet. To be honest, they were so rusty to start off with that any comparison would be flawed. I expect them to work better, though.

ShearPin
01-29-2009, 05:39 PM
My brother and I used TeriAnn's method on some trailer spring packs with really good results. Again, it was a rebuild situation so it's hard to gauge improvement given the state of the spring pack prior. The trailer tracks much smoother with less tug at the pintle though. I would make the effort again.

Regarding the left over friction tape you'll have.... I've used this stuff everywhere. It's tough. Land Rover bodies essentially bolt together - metal on metal. Often the two metals are of different types resulting in corrosion. The friction tape is thin enough and easy enough to work with that it isolates very nicely. I have it between the fender and the breakfast, rear body tub to frame mounts, seatbox to rear tub, etc. No squeaks, no corrosion... :)

Henry
www.4x4freedom.com

Martyn
01-29-2009, 07:00 PM
My brother and I used TeriAnn's method on some trailer spring packs with really good results. Again, it was a rebuild situation so it's hard to gauge improvement given the state of the spring pack prior. The trailer tracks much smoother with less tug at the pintle though. I would make the effort again.

Regarding the left over friction tape you'll have.... I've used this stuff everywhere. It's tough. Land Rover bodies essentially bolt together - metal on metal. Often the two metals are of different types resulting in corrosion. The friction tape is thin enough and easy enough to work with that it isolates very nicely. I have it between the fender and the breakfast, rear body tub to frame mounts, seatbox to rear tub, etc. No squeaks, no corrosion... :)

Henry
www.4x4freedom.com

If you used the tape between two body panels that bolted together would the tape act to seal the two panels against the incursion of moisture?

dustboy
01-29-2009, 07:09 PM
I'd guess the friction tape is the best way to go, but at 5 mil it seems a little thin?? How long before a little bit of fine grit wears through?

I used a graphite-coated canvas made to reduce the friction on the platen of industrial belt sanders. One side is bare canvas, which I epoxied to one leaf, and the other side is graphite flake. After 6 months it's still working fine.

Here you can see it between the main and second (added) leaf.

http://lh3.ggpht.com/_PrLGB0JUQEk/SO1lx-F-YnI/AAAAAAAAAF8/QRXm49MazIE/s800/IMG_2199.JPG

lowenbrau
01-29-2009, 07:20 PM
I'm not convinced the the plastics continue to work after they are filled with grit. OME uses a Teflon pad right at the end of each leaf and over time it loads with grit and wears a pocket into the next leaf. Some people have used slip plate. Its an industrial coating that reduces the friction in chutes and grainbins. I have a set of leafs that I coated but have never installed so I can't comment on long term effectiveness.

cruiseroutfit
01-29-2009, 08:38 PM
I'm not convinced the the plastics continue to work after they are filled with grit. OME uses a Teflon pad right at the end of each leaf and over time it loads with grit and wears a pocket into the next leaf. Some people have used slip plate. Its an industrial coating that reduces the friction in chutes and grainbins. I have a set of leafs that I coated but have never installed so I can't comment on long term effectiveness.

Agreed... however keep in mine the OME pads are greaseable and need to be serviced accordingly.

ntsqd
01-29-2009, 09:50 PM
Posies makes or made Street Rod leaf springs with an anti-friction polymer liner between leaves. Early complaints were of the liner slipping out sideways. In the street rod world there is now a liner material that is a shallow channel shape to overlap and lock onto the leaf itself. Not cheap the last that I knew, which was when this was discussed on the ORC Yota Mini list in the late 90's.

I would encourage anyone thinking about doing this to look at the sought-after-by-most-leaf-sprung-crawlers GM 63" rear leaf springs. Mid 90's to current pick-ups use them. There is a trick there worth noting. There are thin spacers between each leaf & it's neighbors. The only place that the leaves contact each other is at the tips (via a polymer slider) and at the center pin (via the spacers).

Or we could take a page out of Rolls-Royce's 1920's design and wrap the springs with a leather jacket after thoroughly slathering the leaf spring leaves in grease. :)

Robert Bills
01-30-2009, 12:20 AM
Is it worth the time to disassemble the leaf springs and install pads to allow the leafs to move more freely. . .?


In my opinion, unless your springs are already off your rig and your spring packs are already apart, and unless you have a problem with your springs flexing, it is probably not worth the time and trouble for the typical street/trail rig.

"Back in the day," before anyone had heard of teflon pads, about all one could do with a rusty or squeaky spring pack was take it apart, sand and repaint the leaves, and lubricate the leaves during reassembly. My experience with teflon pads and other "slippery stuff" is that they really don't work that much better than a well maintained (i.e., non rusty) spring pack, at least not enough better to justify the time and expense for anything other than a competition rig or extreme rockcrawler.

ntsqd
01-30-2009, 01:47 AM
Contrast that, though, with my needing to go from 255/70 valving to 275/78 valving in the Bilstein 7100's when I swapped in the 63" GM rear springs.

It's the internal friction that makes leaf springs self-damping to a point, so needing to stiffen the damping up indicates to me that there was a loss in internal friction in the springs.
Now that it's not wallowing all over the road as it did with the new (to me) springs and the old damping I think that the spring swap was one of the top 3 mods that I've made to the truck.

I don't particularly like working with leaf springs. They are heavy and awkward, but if there's a ride quality problem that needs to be addressed somehow I think something along these lines is well worth the effort.

cumminscruiser
01-30-2009, 02:52 AM
I think there is a shim between the stock springs. Seems either way I'll take them apart.

Jeep
01-30-2009, 03:58 AM
Most springs in the newer smooth riding pick ups also have a shim approx. 1/16" thick right at the center bolt and about 4-5" long combined with a teflon pad at the ends, there is minimal contact between the leafs and it must work judging from the ride quality of some of the newer trucks (+OEMS spend engineering time and money to come to these decisions).

cumminscruiser
01-30-2009, 04:59 AM
I would hope there is some other way to attach the pads then glue.

UK4X4
01-30-2009, 12:46 PM
"I would hope there is some other way to attach the pads then glue"

On most leaf spring friction pads there's a hole in the spring where the pad locates.

I stripped my leaves apart in venezuela replaced worn pads, added an extra leaf painted greased and re-assembled

Just felt smoother after, some of the original wear pads were worn lop sided
and some were completely worn out

Guinness44
01-30-2009, 01:55 PM
Motorcyclechainlube. Jack up truck on frame, spray, done. But one got to do this pretty often.

RocKrawler
01-31-2009, 01:40 PM
We have the teflon spring pads at work, and the springs we sell have the holes already in the leaf ends that the pads have a snap to locate into - but drilling onto spring steel is a tough job at best, so if you dont already have the holes it would be quite a job to do. Several years ago a friend and I tested the theroy of reducing the friction by also adding small shims between the leafs at the centerpin as well - this produced a nice, small gap along the entire length of the spring out to the pads at the end - it rode and flexed noticably smoother than the stock used leaf and eliminated all squeaks, and no grit could wear anything away like a tape style solution discussed earlier. The byproduct is the extra lift gained from the thickness of all the shims added to the pack making it thicker, which on a spring over vehicle raises the trucks overall height .

Josh
02-02-2009, 03:59 AM
I've done the 5mil UHMW tape on my leaves. It was a lot of work and I don't have any illusions about it lasting once grit is introduced. That said, they really do ride nicer... much nicer! On rough roads my SIIA is a much smoother ride than any of our "modern" vehicles.

Kind regards, Josh

cumminscruiser
02-03-2009, 09:40 PM
Does anyone sell a kit for rebuilding the spring pack? Spacers, shims etc.

ntsqd
02-04-2009, 12:11 AM
snippage......
- but drilling onto spring steel is a tough job at best, so if you dont already have the holes it would be quite a job to do.

A friend of mine stumbled onto what he says (I haven't had reason to try it) is the solution to drilling leaf spring leaves. A hammer drill. Was all that he had so he used it with the normal bit that you'd use in a hammer drill. He claimed that it went through the leaves like they were soft steel.
HTH

cruiseroutfit
02-04-2009, 02:57 AM
I've done my share of drilling, we used to do quite a few "spring flips" with FJ40 springs and we would re-drill the second leaf so that the military wrap stayed at the fixed end. In the end the best practice we found was the iron-workers punch. Sadly the went with the old owner and I've never found quite the need for the investment again.

2talltary
07-20-2011, 04:53 PM
I've been using teflon and UHMW on my leaf springs and it rides a lot smoother than before. I picked up some remnant pieces from http://hightechplastics.com/ and gave it a try and it rides great.

StumpXJ
07-20-2011, 07:55 PM
Motorcyclechainlube. Jack up truck on frame, spray, done. But one got to do this pretty often.


I do this every three months or so. Hit the leaf packs with a pressure washer to get the grit out, and spray the crap out of em. I use Honda White Lithium Grease, works like a champ, and has so far maintained the pads that came on my leaf pack quite well.

Old thread, but wanted to add my two cents.

~ Stump

greasyfingers
07-21-2011, 02:18 AM
Check out a graphite paint called EZ slide, It's often used on farm equipment. I plan on ordering some soon for my new lift springs.

78Bronco
08-02-2011, 03:32 AM
Coils springs?:ylsmoke: