(Home) Front brake caliper bolt

i have a problem where the drivers side brake caliper bolt will not budge.

the head is beginning to crumble, it seems to hve gone soft.

is there an easy way of removing this bolt to replace with a new one, other than drilling?

i can't see how i would have room to get a drill in to it?


steve........

- (#8706) Steve Lewis, 22 May 03 15:04

Hello Steve,

I'd suggest a good soaking of penetrating spray such as TS10 and if the bolt head has disintegrated so badly a pair of mole grips or stillsons on it.

If it hasn't gone too badly then try a socket or ring spanner after giving the head a few bangs with a mallet to loosen the thread.

- (#8707) Mark, 22 May 03 16:42

As mark suggest penertrating oil also keep tapping the bolt head with a drift or hammer this may jar the thread loose.
A good tip. -I always use a ring spanner or socket if possible to get on nut or bolt.
My caliper bolts were tight but came after a few taps.
Hope this helps. Phil

- (#8708) Phil, 22 May 03 17:03

If the head's really bad, try hammering on a smaller socket- like the next size down imperial.The hammering will help, and the tight fit should give you the purchase you need. If that doesn't work, next guess would be find someone with a welder, and get them to weld a nut onto the head of the bolt. The heat helps, then you can get a good grip on the new hex head.

- (#8709) david miller, 23 May 03 1:23

If you need to drill it, you can see the thread end on the outside of the caliper. Be aware if you go that way that you may damage the thread in the caliper.
If the end has rounded itself, i'd try getting a flat edge (any excuse to use the grinder), and getting a pair of stillsons on it.
Replacement bolt is Toyota part number 47707A. Used on many Toyota's so should be over the counter no six week waits.....

- (#8710) Clive, 23 May 03 1:39

Just got off the phone with my local Toyota dealer.
(Canterbury)

The part number above is incorrect.

I am waiting for a call back to see if they can get them, as they don't keep them in stock.

I will post the part number when I get it.


Steve....

- (#9027) Steve Lewis, 7 Jun 03 5:01

Clive gave the PNC, the actual number is 90119-08384 for 2wd, 90119-10385 for 4x4

- (#9028) david miller, 7 Jun 03 7:32

Sorry Steve stopped a screen short on the CD (to busy finding other models that it fits), thanks Dave for pointing that out.
- (#9029) Clive, 9 Jun 03 3:28

I just had front brakes done on my 2001 Toyota Tacoma (4x4). My mechanic said the caliper bolt needed replaced on front-driver's side. I told him that the only way a caliper bolt would need replaced on a truck this new (with 25,000 miles) is if he stripped it the bolt. The brakes had just been done 7 months ago, and now need replaced again. Sounds to me like the bolt was stripped going in the first time, causing the brakes to wear so quickly.

My mechanic says the brakes were fine when done 7 months ago, that the bolt corroded during the last 7 months (causing the pad to wear) and he had to replace it to do the brakes again. He also said this caliper bolt is not threaded, but is a straight pin, and could not be stripped.

I would appreciate anyone' expertise on what might have happened.

- (#10138) Tom, 9 Aug 03 11:36

yup, the caliper slides on a pin. Sometimes a bolt screws into the end of it, sometimes it's a pressed- in part of the caliper, depending on model. Sometimes the bolt itself is threaded at the head and has a long straight guide section.
A couple of things can cause problems- wear of the thread, wear of the head, the sliding section, corrosion of same. The corrosion may be caused by a failed seal at the end of the slider. Anything which stops the caliper from sliding smoothly WILL cause the pads to wear out. Are the roads salted where you are?

And bear in mind that some bolts have to be replaced every time they're removed!

My advice to you is to trust your mechanic. If you know as much about it as he does, why don't you do it yourself?

- (#10139) david miller, 9 Aug 03 11:48

Tom. Adding to David's expert advice, this "bolt" is really a guide rod, or pin, and should not be confused with the securing bolts which hold the caliper assembly on to the hub unit. There is normally a "boot" which retains the lubricant (grease) which stops the pin and caliper from corroding together. There is such little movement that they do corrode, or lock, quite easily and you might find that the rubber boot has failed, causing the lubricant to be washed out. These guide rods can easily be cleaned up and re-greased but, your mechanic obviously thought that it would be cheaper and more efficient to replace the rod/pin.

- (#10140) John Davis, 9 Aug 03 12:04

Boots, pin and bolt all available from toyota as single items and moderate cost.

- (#10141) Clive, 10 Aug 03 1:42