The brakes are applied the front brakes lock up

ANONYMOUS

MEMBER
1993 FORD F-350
370,000 MILES

I have a 93 f-350 tow truck, when the truck is loaded with a car and the brakes are applied the front brakes lock up, when unloaded the fronts lock up when applied hard. What could possibly be the problem with the brake system?

Saturday, October 27th, 2012 AT 7:04 PM

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

We need to start with finding out if this is both front wheels or just one. This is caused by either the caliper or master cylinder. So, we need to inspect both front calipers for sticking and make sure it is not the caliper.

https://www.2carpros.com/articles/brake-caliper-replacement

https://www.2carpros.com/articles/how-to-replace-a-brake-master-cylinder

If the calipers are not sticking, then we most likely have a master issue.

To check the calipers, remove them and use a c clamp or vise grips and push the piston back in and it should go easily and smoothly.

The only other thing this could be is an ABS issue but if it is not activating as you didn't mention anything about that then I suspect we have a master issue.

Please see the info below and let us know what you find. Thanks

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