Need your opinion on spring leaf lube

[billybob]

I've taken my leaf springs apart,blasted them,primed them now ready to paint. My question is - when I assemble them should I use some sort of lubricant or dry silicone or just assemble them dry? Dry graphite may help if I could find enough. I'm glad I took them apart because they had a lot of dirt, sand and rust buildup. It was one of the most boring jobs of the whole project. It takes a while to do 42 leaves. I do know better than to use regular grease. Thanks again for any advice.

[wesk]

The majority response in the last several times this question was posted answered: "Nothing to go between the leaves!".

I tend to agree with that.

[billybob]

Thanks again Wesk for the good advice.

[jaycee]

thats an interesting topic.if you search it on the web you will get opinions on both sides of the fence.and it do go on and on. people at eaton spring say that the steel used in the springs nowadays is affected adversely by grease. i find this hard to believe, but my skepticism is not a useful argument. ill say two things though,my 1940 chevrolet had a metal jacket with a zerk to grease the rear leaves. i lived in hawii on an outer island for 18yrs and saw people coat their springs with all sorts of concoctions grease,grease mixed with gear lube,etc. i never saw or heard of a spring failure on a lubed spring.i wont say that eaton spring or anyone else is wrong i just cant confirm it. i saw plenty of springs though. corrosion had gotten so bad on a m38a1 that the outer spring wraps corroded away and the rust forced the springs to fan out on both sides of the axle. so i guess it depends on where you live,what sort of service you are planning for the truck and what you choose to believe

[wesk]

If you research the issue carefully you will see the bottom line is the engineering design of the spring set.

If the inter-leaf friction is important to proper spring function and rate then no grease. Greasing this type spring set would have an adverse effect on performance.

The best source for weather to grease or not is the manufacturer's manual lube recommendations. The applicable M38, M38A1, M170 TM's and the equivalent civilian service manual SM-1003 show no requirements for leaf lubrication.

[STXM38A1]

Per TM9-8015-2, upon assembly "........and placing powered graphite between spring leaves, ........"



I had an old note that someone previously recommended Slip Plate #1 for springs when overhauling/restoring.
http://www.slipplate.com/pdfs/DATA-SLIP_Plate_1.pdf

[billybob]

Thanks to everyone for the very interesting information. Today I talked to a friend of mine who has a business restoring old cars, his specialty is ford retractable hardtops. He told me he has serviced a lot of leaf springs and re-arched them. He told me if I use a lubricant I would have nothing but trouble. I'll have to go with wesks suggestion and assemble them dry. I'm not worried about rust because about the only time they will get wet is when I wash it. Maybe once in a while on the road. Thanks again for all the help. - Robert

[wesk]

Warren,

Interesting find. I haven't looked at the A1 8015-2 in a few years. So then yes one of the M series manuals does mention lubing with graphite. The other three do not. Nor do the civvy manuals covering 1950 through 71.

[BullRun]

One of the surplus parts dealers told me this story...

The original M38A1 leaf springs are the version with a tapered edge and at some point the original manufacturer went out of business and that style of spring became unavailable.

Another manufacturer was found and new springs became available again. However they had a different design. These new springs had a groove in the leaf. The groove is there to hold grease packed between the leaves.

They are also considered military replacement springs. They are not aftermarket.

I have both styles of springs on jeeps but have never seen any of them greased.

[billybob]

Bullrun: Thanks for the info. The leafs on my M-38 have tapered edges but no groves. I believe I will just leave them dry. I'll let the paint and primer be the lubricant.