Toyota 1993 pickup loud sound when braking
 

Hello y'all,
So I've been having a issue with my toyota and thought I would see if y'all have had this in the past.
I took my pickup to my mechanic about 6 months ago because it was having a problem occasionally that I thought was caused by the clutch not engaging properly. Basically when it was acting up I would have rough shifting when going into the lower gears, especially from a stop. When it was really a problem it felt like I was trying to shift without my clutch to the floor and once or twice it make the grind sound that no one wants. Whenever this would happen I could take my foot off the clutch and re-engage it once or twice and it would fix the issue. When I originally took it to my mechanic he said that he could not find the issue (which I told him only happens every couple trips to town) but that he could check on my clutch/ transition anyways. Somewhere along the line he found some troubles with the throw out bearing and while replacing that he found that the clutch was bad. Now both are replaced. After this happened I noticed the shifting was much better and was only a little hard to shift now and then. The problem wasn't fixed but I was out of funds to invest for the time being so I thought I could live with it for awhile.

About a couple months ago now I noticed that randomly it was beginning to have trouble with braking and it has started happening more and more though it is a off and on issue. Basically what happens is when I am just about to come to a full stop the the truck will make a shutter sound exactly like I do not have the clutch in. It will continue to do this several stops in a row and then go away until a couple trips to town later when it decides to be stubborn again. I know it is not how I am pressing the clutch because I do not have a mat or anything else in the way and if I press any harder my foot will go through the floor..... I took it back to my mechanic but he drove it and said there is nothing wrong with it.

A couple other details that may help is that I can tell ahead of time if it is going to happen because I can feel it in the clutch. When it is going to shudder the clutch feels like I am pressing down nothing. Almost like I am pressing a lever that isn't attached to anything. Also, The other day it finally happened while I was in my driveway and I was able to play with it a little. When I tried to shift I could take it out of the 2nd gear but I could not put it in gear without the "clutch isn't in" sound. Pressing harder or moving the clutch pressure around did nothing to fix it. Then I took my foot off and re pressed and it shifted and braked with no issues for me getting into my parking spot. Lastly, when this issue is going on I am also having trouble shifting into lower gears.

I feel like my mechanic thinks I can't drive and that I can't brake in my truck or I will kill my transmission...... Do any of y'all have any thoughts? I wish I was able to work on the thing myself but I only have the knowledge for minor projects that don't involve major parts like transmissions. Thanks of any help with this.

Sounds like the clutch's actuating system. The clutch master and/or slave cylinders. If it were me, I would bleed the system to check for air, and totally replace the fluid at the same time. Just bleed it enough to totally drain the master cylinder, but do NOT let it draw air in. Keep adding fresh fluid (DOT 3 brake fluid) to prevent the intake of air.

If there's no air, it may well be time to replace the two cylinders. Not that expensive, or difficult at all. Also, check that the mount where the pedal is attached to the area under the dash isn't cracked or broken. They're known to do that. The metal piece the pedal swings from.
You might also check that the pedal's alignment is correct IAW the FSM.

If it's not any of that, is the arm that the slave cylinder pushes on to disengage the clutch is cracked, or otherwise broken? If not, maybe it's time to replace the clutch.

Keep us appraised of your progress! That's my supply of big words for the day...:laugh:
Pat☺

Thank you for your help. I did just get the clutch replaced but I am not sure if the cylinders were checked. I believe he did change the fluid when it was replaced but I can double check on that. Do any of y'all think it could be a issue with the clutch part from O'Reilly? I haven't heard a lot about the clutch parts from there failing but I have had other parts from them cause problems and I was worried ordering such a important part from them.

I don't know about O'Reilly parts, but in this case, if it were me, I would definitely only allow OEM parts.
Having said that, I wonder if maybe the throwout bearing either wasn't installed correctly, or was damaged somehow.
Did they resurface the flywheel while everything was apart? That's a little something some places miss, but is pretty important.
Is it possible they put the clutch disc in backwards? You laugh, but it happens.

I also would still bleed the system real well, and check for the cracked pedal mount, as well as the fork the slave cylinder pushes against. First and foremost, though, definitely bleed it out. It's easy to have gotten air in there, and easy as heck to get it out. It might just be something that simple...

Let us know how things work out!
Pat☺

Thank you, I am going to bleed the system as soon as I get the time this coming week. I'll also see if my mechanic can look over the system for problems. I'll post with updates as I get them.

Second this^^^
My local O'Reilly clerk was actually able to find Aisin replacement for me for same price as after-market I returned to store for a leak within a few months of install.
So, O.P., take your time and shop thoroughly.

Alright, After 3 weeks in the shop my mechanic ended up replacing the clutch fluid and the clutch master cylinder. The pedals were checked for cracks as well. I wanted to replace the slave cylinder at the same time but he had started finishing up with my toyota by the time I knew since I was at work so maybe next time. Since this part has been replaced I have noticed a huge improvement and haven't had the issue. It did shudder once but I'm going to just keep a eye on it since it is driving great and the slave cylinder still could use replacing. I believe it was the clutch cylinders causing my troubles so thank you for all the help!

The slave cylinder is easy to replace. Just a couple bolts, and the fitting for the fluid. Replace the cylinder, refill with fluid, and bleed it out. Boom, done. When you undo the fluid fitting, you will loose a little fluid, but you can just plug it off, and keep the fluid in. That keeps air out of the master cylinder. Once you get it reinstalled on the slave cylinder, it's very easy to bleed the air out. Just make sure the master cylinder has enough fluid in it at all times, so it doesn't get any air in it while bleeding it out.

Good luck!
Pat☺