How to remove rear caliper carrier bolts?

I have been struggling with this for a while now: The two Allen headed bolts that hold the rear caliper carriers (abutments?) to the axle do not want to come out. I can't get a driver straight in there, and an Allen key doesn't allow enough torque. I've started stripping out the head, so I am really getting worried.

I haven't tried torching the axles yet.

Any tips/tricks?

TIA!

I always use a good 8mm 3/8" short allen bit with a universal going to a 3/8" to 1/2" adapter and a nice strong fully charged compressor/air gun combination. Make sure the bit is hammered into place and slowly build to full power on the gun.

This usually works, if seen them where the guy before my stripped them into place and in that case, when this happens you need to take the sheetmetal piece off allowing greater access, I've even dropped the lower strut bolt to drop the axle... If you have ABS, be careful with the heat or you'll be buying a new $100 speed sensor, sometimes can't really get that sensor off without having the caliper carrier off too, so keep that in mind, kinda chicken and the egg thing there. I've had them with 1/2" breaker bars and cheater bars before breaking them free. If it's stripped, you're on your own, it might have to get messy before it can be cleaned up.

A sharp air hammer chisel placed at just the right angle on the side of the fastener has done wonders before as well. You're obviously going to replace them with new anyhow.

Hope that helps, the fact that they are self locking isn't helping your situation.

If your straight driver isn't the right size to get in there, you may have to make it the right size.

I use a short 8mm bit with a small wobble extension on a 3/8" ratchet with a long handle. I tap the bit in place with a small hammer before trying to loosen it. If it won't move, I try to tighten it a tiny bit, and then it usually comes loose.

Small thread hi-jack.

When reassembling is it okay to use never seize on those bolts? When I did mine, I had to use the chisel method on one. Just want to know for future reference.

I swear the VW assembly workers torque those bolts to 250ft-lbs or when they're friction welded, whichever occurs first.

The first time I took the rear calipers off it was a royal PITA. My 3/8" bits and ratchets were too short to get any leverage. My 1/2" breaker bar was too long and I couldn't get the car high enough off the ground to give the bolts a good fast jerk to break them loose. Finally after scraping my knuckles, almost breaking my bits, and stripping out the bolts, they broke loose with a very loud CRACK.

When putting the rear brakes back together I used new bolts and YES, I doped them up good with anti-sieze paste along with all the nuts & bolts. Every brake job after that was as smooth as butter. As I recall those bolts only need to be torqued to around 45ft-lbs.

Good luck.

.

*@#&*@@ Rear carrier bolts!!!

I had the same problem and after liberal soaking with PB Blaster did not work, used a propane torch to get it hot, then hit it with PB Blaster, then same as above...tighten a little, then loosen. This worked for one and the other bolt I simply twisted the head off! Ditto with never seize! Use with reckless abandon!!! My rear carrier was bent just a little....gift from the previous owner, so it had to be replaced.....just one of the many joys of getting a 9 year old car back into great running shape! Good luck!

bump for 8mm and wobble extention. Proper torque for those is only 52 ft/lbs (or is it 58?), so no need to torque them to death. I usually use loctite blue on the threads - it will keep the bolt from backing out, but also it will seal the threads against moisture so they shouldn't rust into place, making the next time a far more pleasant experience.

Mine did the same thing. I tried everything I could, and finally went to a friend who works on high-end Land Rover restoration (some of the their restorations/mods are in the $300,000 range). We put the car on the lift, dropped both struts so the axle beam was hanging, removed the e-brake assembly from the way, and used a 1/2" IR impact fun on full power to break them free, and then they did not want to come quietly.

They're liberally lubed with never-seize now and I've redone the brakes many times with no issues.

I own a right able drill because of this same problem. You might find this thread interesting: http://forums.tdiclub.com/showthread.php?t=260657

My first post in this thread was about the rear brakes on my 97. This time it was my 96.

This time I gave up and took the car to a shop. They used their longest 1/2" breaker bar with a 3' pipe extention. They had the car up on the rack to get proper clearence and were getting nervious at how much the bar was flexing before the bolts broke loose. With a loud CRACK all 4 bolts broke loose.

The new bolts go in and out like butter. Anti-sieze is your best friend when it comes to those carrier bolts.

york77777 said:

Anyone know the p/n for the carrier bolts on an a4 jetta rear? Or where I can get them other than worldimpex or dealer?

Click to expand...

A part number for a bolt is for people who like to wait on special orders to come in. Not me: You need the "Grand Master" of metric hardware. Here's what you do.... Mic the old bolts and determine the thread diameter and length in millimeters. Use a thread gauge to find the thread pitch and then go to http://www.Belmetric.com. These guys have bailed my bacon on more than several occasions.....they're fast, local and Ralph really knows his sh*t. You are looking for grade 10.9 hex or ellen flange bolts

GetMore said:

I have been struggling with this for a while now: The two Allen headed bolts that hold the rear caliper carriers (abutments?) to the axle do not want to come out. I can't get a driver straight in there, and an Allen key doesn't allow enough torque. I've started stripping out the head, so I am really getting worried.

I haven't tried torching the axles yet.

Any tips/tricks?

TIA!

Click to expand...

Those can be a real mother to get out. I'm surprised I haven't heard this yet but when I run into a situation like this on a stripped out 6 point ellen head fastener, I hammer the next biggest size XZN or triple square bit into it and usually with no heat or PB'laster it will turn out with the same degree of positive head engagement of a new 6 point ellen. One of the better reasons to have short unsocketed triple squares handy.

Be sure to hammer it in good until the pitch of the hammer ring changes and once the triple square spline is set, don't mess with it save only to apply left hand torque after you've gotten situated to apply brutal force to it. You've only got one REALLY good shot at this. I've had a 95% success rate with this method so long as you DO NOT apply heat, but do use PB'laster. Lastly, toss any and all cans of WD-40 right in the garbage
Good Luck

Dave

Been reading threads like these and asked myself "What the heck are triple square spline bits?" Sounds like I need to go shopping for some new Tools for the Tool box. I never need much enticement to do that!

warbird24: They are basically a slightly different Torx bit. I chose to buy Snap On as I find them less prone to round things off. That and I tried the AutoZone version and the correct one for the axle nuts shattered as soon as I put torque on it.

Does anyone know the part number for these bolts? I need to order 1.

Part number N-907-294-01, M10X1.25X21 are the dimensions. I'd highly recommend you order enough to replace all of the ones you remove. These often get destroyed on removal. As cheap as they are, I just stock them and consider them a one time use part.

Just curios if people who live in the non rust belt still have this problem. I did mine and they came out with no problem. Vancouver BC. No salt used on roads as little snow.

My B4 was bought and driven in Florida up until I bought it about 4 yrs ago. Those bolts were a major PITA to take off. Used a grinding pad on an air powered Dotco to cut off 1/3rd of the bolts head and give us a flat spot to work with. An air chisel against that flat spot and some major time with penetrating oil was how mine we're broken free.

I haven't had a need to replace the rear brakes, yet. At least I can order the bolts ahead of time.

TIA

Tony

Here's a little trick to help deal with allen wrenches slipping in this type of 'stuck' fastener. Put a small (small!!) quantity of valve lapping compound on the flats of the wrench before inserting it into the socket. The cutting compound greatly increases the friction between the wrench and the bolt's socket and helps to prevent slippage and rounding out of the socket.

Start with a clean, dry socket, apply the trick above and these bolts should come out OK.

Good Luck!