Toyota Previa Front Brake Problem

Johnboy63

Hi folks --- I have a problem with my 1997 toyota Lucida Estima (previa) -- It shudders significantly on both front wheels when I brake -- badly at higher speeds !! It's as though the pads are gripping firmly on one side of the disks & poorly on the other with a resulting jerky reduction in speed. (Does effect an emergency stop). The disks were replaced on it when we got it first as attempt to resolve the problem with little results. I have checked the sensors behind the each of the disks -- they are clean etc. The problem only seems to be present on the front brakes -- rear brakes are functioning normally !! Can someone please enlighten me as this is driving me mad & I can't imagine it's entirely safe or the best for the car in-that it shakes the car quite a bit !! Any help by way of advice would be much appreciated.

Atlantic Dawn

I presume the pads were also replaced with the discs?

dunsandin

Get a mechanic to check the run-out of the discs to ensure they are sitting flat on the hub. A build up of crud(even a small one) can cause the discs to run at a wobble. The dial gauge will show this up. If they are not running true, sand the mating surface to get a flat seat. Also dont eliminate warped discs due to binding of the caliper pistons-the car is no spring chicken, and they are a great motor, but not infallible. The pistons may not be retracting correctly on one side, and the resulting heat build up can rapidly cause warping.(me missus has a 2.2 diesel prev, and its a great car.) Personally I'd be betting on the discs not sitting flat on the hub, but the calipers could also be a bit suss.
Failing that, get shoes with really thick soles and wear 2 pairs of gloves so that you dont feel the vibrations. And before I get accused of being schnide, thats a joke ^^^. ds.(or at least it is to my warped sense of humour((a bit like your discs-may cause annoying vibrations))

Johnboy63

Thanks guys !!
Atlantic Dawn --- Yep the whole job lot was replaced by the mechanic for the guy who sold us the car. The problem appeared to almost completely disappear only to return when it had gone out of warranty. Thanks a million!! Don't be depressing me with financial stats like that Anglo stuff !! I might get personal with a member of the government or a banker in high places !!!!

Dunsandin --- Ditto thanks a million --- I wouldn't dream of accusing you of anything other than being a guy with a good healthy sense of humour --- God knows we all need that nowadays !!! Yeh I might get to it one day real soon & strip them both out & clean everything right back & then reassemble them both see if they seat back in a more true position & have a look at what you've said !! As you said they are a lovely car --- I replaced the engine in it last year as the cylinder head cracked (brute of a job) & the cheapest option was to replace the entire engine --- dealt with a guy in UK & made enormous savings !! I have the address of a guy in UK I found on e-bay & his prices for parts are amazing compared to Irish ones. Never again would I buy here --- we're being screwed royally in Ireland for parts !!!!! Example -- I drive a 20 year old Merc 190e 1.8 petrol -- priced a rear exhaust silencer box for it in Dublin last week at €210 --- I can get the part in UK for £40 & carriage of £20 -25. That doesn't make me want to buy here. I don't have them to hand right now --- but if you want the addresses let me know. Much appreciated guys --- I was working last night for eleven hours so I'm off now to put my head down, where I hope to find it later this evening, so I can go & do it all over again tonight !!
John J.