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Old 05-08-2026, 08:26 PM
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433lemans 433lemans is offline
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Default 69 Lemans Front Coil Springs Replacement

So I'm finally back to converting my front drums to disc brakes. I'm also installing new coil springs. As pictured, the original springs have the top tapered to give a relatively flat contact surface. The new springs are not. Should I grind the new spring so it is tapered also? Looks like it could wear into the spring pocket if I don't do something.
Has anyone here dealt with this, or do I have the wrong springs?
Seriously looking for suggestions. Asked in the Suspension section but no replies.
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Old 05-10-2026, 12:33 AM
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Tuske427 Tuske427 is offline
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I've personally never had any trouble with coil springs like this. If you're concerned you could radius the top corner of the spring (removing a lot less material & minimal heat build up than grinding half the top coil flat) to eliminate the corner edge and any potential gouging. not that it would be moving much anyway... it's under a fair amount of pressure when compressed. The last thing you would want to do is build up too much heat and destroy the temper of the spring- then it would cease to be functional.

You could also call up a company like Eaton Detroit Spring and talk with their people to see if they say differently.

hope this helps

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Old 05-10-2026, 12:58 PM
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hakansan hakansan is offline
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I can´t see the 5390 listed for a Lemans in 1969.
I would think the 5372 would be correct.
Anyway the replacement spring for Your car from Moog don´t need any modificatition.
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Old 05-12-2026, 10:45 AM
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All replacement springs have this issue, apart from never providing the correct ride height the non tapered spring top tends to make the spring have a "bow" to it which can contact the frame causing annoying noises when turning quickly.

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Old 05-12-2026, 08:29 PM
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Thanks north. Food for thought.

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Old 05-12-2026, 10:21 PM
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It just looks like the top couple of inches of the new coil, especially the very end would excessively wear into the upper spring pocket compared to the original spring.

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Old 05-13-2026, 12:08 AM
propuckstopper propuckstopper is offline
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Quote:
Originally Posted by 433lemans View Post
So I'm finally back to converting my front drums to disc brakes. I'm also installing new coil springs. As pictured, the original springs have the top tapered to give a relatively flat contact surface. The new springs are not. Should I grind the new spring so it is tapered also? Looks like it could wear into the spring pocket if I don't do something.
Has anyone here dealt with this, or do I have the wrong springs?
Seriously looking for suggestions. Asked in the Suspension section but no replies.
I bought original height, exact factory specification front springs for my 1968 GTO from Coil Spring Specialties. Just like your original springs, mine are flat on the top.

As I have said here before, if you are looking for cheap, don't go to Coil Spring Specialties. But if you are looking for first-time fit, they are well worth the extra money. They are made in the USA from original GM blueprints.

I have answered several threads here on the board and have always recommended CSS. I have CSS springs on both my 1965 and 1968 GTOs and they can't be beat. The last thing I want to be doing is flipping out front coils from other manufacturers that are not right. The potential injury is not worth the discounted price to me.


Last edited by propuckstopper; 05-13-2026 at 12:14 AM.
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Old 05-13-2026, 01:32 AM
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If you stand the coil spring up on a flat surface, and it doesn't tilt but is straight up from the ground, how is it going to dig into something ??

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Old 06-21-2026, 03:50 PM
Joe's Garage Joe's Garage is offline
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Default OP is talking about the TOP of the spring not being flat

Original springs will stand up on either end.

His replacement spring would not because of the non-modified tip.

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