Car Pulls Left after Bleeding Brakes?

[HyperV6]

Summer 2022 I rebuilt the entire front end on my car - new bushings in upper and lower control arms, tie rod ends, center link, idler arm, rebuilt steering box, repacked the inner and out wheel bearings, and installed new Hawk brake pads. I bleed the front brakes only just to make sure everything was working correctly. I did not turn the rotors when I installed the new pads since the car went straight when braking and had no noise or vibrations. I replaced the Hawk pads on the car with the exact same Hawk brake pads. About 10 years ago I installed new rebuild Cardon front calipers and Classic Tube braided stainless steel brake lines on the car - I just reused them since they were working fine. After I broke in the new Hawk pads per the instructions, the car would pull left when braking. The faster and harder you brake the more left the car wants to go. I have to steer to the right to keep it in the lane. I tried lubricating the caliper bolts again and bleed both sides of the front calipers a second time - no air in the system and the fluid seems to come out just fine when bleeding. Over the next few months of driving (500 miles) it seemed to get better but never 100% straight when braking.

Yesterday, I replaced the rear brake shoes. I then decided to the bleed both rear wheel cylinders (8 to 10 years since I bleed them) and bleed the two front calipers. Well, it's pulling hard left again when braking. 40 mph or above it pulls pretty good left causing me to steer to the right to try to keep it within the lane. So, it seems the brake bleeding has caused it to happen again.

Any suggestions on what to check? The front left caliper is grabbing first and harder I would thnk.

Thanks, Craig

 

[mblum]

Summer 2022 I rebuilt the entire front end on my car - new bushings in upper and lower control arms, tie rod ends, center link, idler arm, rebuilt steering box, repacked the inner and out wheel bearings, and installed new Hawk brake pads. I bleed the front brakes only just to make sure everything was working correctly. I did not turn the rotors when I installed the new pads since the car went straight when braking and had no noise or vibrations. I replaced the Hawk pads on the car with the exact same Hawk brake pads. About 10 years ago I installed new rebuild Cardon front calipers and Classic Tube braided stainless steel brake lines on the car - I just reused them since they were working fine. After I broke in the new Hawk pads per the instructions, the car would pull left when braking. The faster and harder you brake the more left the car wants to go. I have to steer to the right to keep it in the lane. I tried lubricating the caliper bolts again and bleed both sides of the front calipers a second time - no air in the system and the fluid seems to come out just fine when bleeding. Over the next few months of driving (500 miles) it seemed to get better but never 100% straight when braking.

Yesterday, I replaced the rear brake shoes. I then decided to the bleed both rear wheel cylinders (8 to 10 years since I bleed them) and bleed the two front calipers. Well, it's pulling hard left again when braking. 40 mph or above it pulls pretty good left causing me to steer to the right to try to keep it within the lane. So, it seems the brake bleeding has caused it to happen again.

Any suggestions on what to check? The front left caliper is grabbing first and harder I would thnk.

Thanks, Craig

If the brake system has not been opened a full bleed may not be nessesary but when I run into issues like this I usually start over bleeding the whole system. Starting at the cylinder furthest from the MC and work to the closest. I bleed rear passengers, rear drivers, front passengers, front drivers.

The rear drum adjustment screws at the bottom plays a role in bias from drivers to passengers side. To get this dialed in I found a cheapie infrared temp gun like what harbor freight has is very useful. Drive the car in regular conditions and pull into a parking lot and note the temperature of each drum.

Recently when I replaced my rear cylinders I had an issue where my car would pull, temps were about 20 degrees different. Adjusted the drums and got them within a few degrees and no more pulling. This temp gun can also be used on the front rotors.

May be worth double checking all front caliper pins and making sure the fronts are releasing fully.

 

[steve hughes]

try gravity bleeding the brakes. It takes a while but usually helps.

 

[HyperV6]

Thanks for the advice guys. I finally got the time to work on the car today. My driver side drum was tighter than the passenger side. I adjusted the passenger side about 8 more clicks. They them seemed to take about the same effort to remove the drums off the shoes. I drove the car around town for about an hour. The car seemed to improve about 80%. I did take your suggestion "mblum" and bought a temp gun. After some driving and spirted braking I took some temp measurements of the drums. I seem to have them within a few degrees. I am going to do some more driving and hopefully once the brake shoes get a little more broken in it will track straight when braking sudden and hard - it's much better now.

Who would have thought the rear drums would have made this much difference. Thanks again for the help. I'll post again when I get a few more miles on the new brake shoes.

Craig

 

[mblum]

Good to hear you made progress. Another item that can causee pulling on the fronts that I forgot to mention is the possibility of one of the flexible brake lines either collapsing or expanding under pressure due to old age. If one is replaced in my opinion both should be replaced at the same time.

 

[HyperV6]

I replaced the original rubber lines in 2013 with Classic Tube - braided stainless Teflon lined hoses. I sure wouldn't think those are bad. I do some more driving and post the results.

Thanks, Craig

 

[HyperV6]

Guys, I did the shotgun approach. I replaces the front rotors with EBC stock replacements, front calipers (I rebuilt my origin factory ones), and new Hawk HPS pads. Car stops straight now and no pulling to the left. Never figured out the cause of the original problem but probably the calipers.
Thanks, Craig