how easy is it to change the callipers on the back with the sub frame still attached to the car
1984
It’s doable, but trust the advice of EVERYONE who’s done it: It’s EASIER to drop the subframe.
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It’s like trying to paint a room without removing the furniture. Awkward!
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It’s a bit like trying to paint a room with a roller, but you’re standing outside in the hallway.
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I have done it both ways and I can tell you it is so much less work to just take the cage out.
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I am with Kerbert, It is way easier with the subframe out. The first time, I tried replacing the brakes with the subframe in the car, it took 8 hours for me to get one caliper off. JUST OFF!, I asked the yoda’s of this forum, and they said DROP THE SUBFRAME. It I seemed like a daunting task, but the subframe comes out very easily, a couple of pointers. it’s really heavy about 350lbs heavy. you’ll need to get the ass end up at least 24 inches for enough clearance for a trolley jack and the cage.
Here’s a couple of reasons why to drop the subframe.
- With the subframe left in the car your work area is severely limited, like a 1/4 turn bolt / nut on these wonderfully fine threaded bolts. you’ll be loosening bolts for what seams like eternity.
- If the brakes are shot, then more than likely the diff seals and rubbers are too (at the very least). It’s not a bad idea (actually a really good idea) to at least replace the diff seals.
- It’s been my experience that this is where the process turns into an onion. (depending on mileage and previous maintenance) as you strip away (complete) one maintenance item, another pops up right behind it. Like layers of an onion.
The bottom line is this, if the brakes are done for, more than likely it’s time for a IRS rebuild meaning check tolerances, replace or grease bearings, and replace all of the seals and rubber bits.
Word of caution, When you start down this journey, have a camera handy to take pictures of where stuff goes, there are a bunch of needle bearings and washers (shims) of different sizes, and they HAVE TO GO BACK in the exact order in which they came from. I have a shop manual so I will help as much as I can from here.
if you take the yoke off, BEFORE you loosen the bolt, use a chisel and mark the nut, and yoke, to its position in relation to the housing to ensure you get the proper tension is put back on the crush washer (bearing). The nut that holds the yoke on, also sets the backlash for the ring and pinon gear.
I hope I didn’t scare you off. If you pay someone to do it, you’re looking at a $3,000 US dollar bill. I did that too. ouch!
Cheers!
Mark
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And remember: If you’re servicing the inboard calipers, IMHO you should be upgrading to vented rotors.
http://www.jag-lovers.org/xj-s/book/InboardBrakeUpgrade.html
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wow! they want a bunch of money ($800.00) for the rear vented rotors. Too rich for this cheap-ass. I’ve got solid rotors on all my Jags except 1 (the X308 doesn’t count) and the '85 still has the pie plate multi-layer rotors in my '85 XJ6.
I do have a set of Brembo vented and slotted rear rotors. in a box someplace.
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What’s this “they” stuff? The Wilwood rotors barely cost any more than OEM rotors.
It’s more fiddly getting the small stuff together, but the cost difference is minimal and the improvement in diff output bearing life is well worth it.
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Good to know, I was looking at XKS and Terry’s jag prices. which were well into the $700’s. I checked out the link, but there’s some important bits missing; like how it mounts to the half shaft. If I can find that for cheap, I’ll be using the willwood rotors for my next brake job(s). I’ve got about 3 of them to do right now; and not the fronts either. Ugh!
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Probably worthwhile to read the entire page. I know, it’s wordy, but I tried to give people all the options. Yeah, you gotta fab “hats” to use the Wilwood rotors, but that’s just a matter of printing out the diagram and handing it to the guy at the machine shop. You’ve got to fab a few other odds and ends, too, but they’re pretty easy.
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Have you used these rotors?
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I developed the procedure! Well, in a way. Kits were out there, including GTJ’s pile of garbage. And the TWR uses virtually the same scheme to provide vented inboard brakes. But there were problems with many of these packages, so I went through the design and corrected the errors. The setup I installed in my '83 bolted right in and worked great. The only grinding on OEM hardware required was on the inner end of the lower swingarm to permit it to swing around the corner of the wider rotor, as mentioned on that page.
Frankly, the biggest PITA is that bronze fork on the handbrake caliper. Dealing with that thing is fiddly – but hey, it’s fiddly dealing with the stock fork!
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If you really want to test your own abilities do it with the subframe in. I made up a special spanner to crack off the mounting bolts and after that you have to unscrew 1/8th of a turn at at time. When you eventually manage to remove them then as it says in the good book “the installation is the reverse of the removal procedure”. Prepare yourself for several hours of toil because getting the calipers located and the bolts in is just awesome.
Next time I’ll drop the subframe.
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When I got the car 24 years ago I remove the rear calipers in situ to recon the piston and rubber’s, I got it all off but couldn’t get that bronze spring for the hand brake back. In the end I removed the s.f. But driving down the M3 the other day I had a brake peddle that went to the floor 2 times which is scary at 80 90 mph on a British motorway. I have replaced both fronts in the last 12 months from Wards so it must be the rears. Really I just wondered if anyone had come up with a new way of doing it. I’ve done13000 miles in the last 24 years so uk home concrete and asbestos garage is a bit damp in the winter just sitting there unused, for 7 months every year. I’m 71, fit but have lost the enthusiasm that I once had. But it will be done
If you have not lost any fluid, more than likely it is the master cyl seals failing, I know of many peope who have had this happen, including myself.
imo, the brake master cylinder seals need replacing every 10yrs ideally, eventually they become soft and bypass. Sometimes that fluid will end up in the vacuum booster,
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The thing is they are always good locally and once that soft pedal happened, for the next 200 miles that week and since, it never happened again.
I did fit a brand new master cyl. 10 years ago ish, they are, evidently the same as on old Chrysler Avenger. A well obsolete uk brand.
from what I have experienced and seen/heard, if the pedal goes to the floor, but either responds to pumping, or becomes “good” again, that is a master cyl seal bypassing
if an individual caliper seal fails, and the pedal goes to the floor, that will mean the seal is wrecked and will continue leaking (had that too)…till all the fluid runs out even!
the standard fix over here is either a new seal kit, whole MC, or SS sleeve, which I have had done several times, it is cheaper and last a lifetime (still need new rubber seals periodically)
very unnerving have that kind of brake failure, and since it happened to me a couple of times, am fussy about brake maintenance
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Interesting. Do you have the Chrysler Avenger part number?
Jim 1984 XJSC 3.6 manual Brighton UK
Yeah, that sleeving is simply awesome – if you can find anyone that does it any more. Nowadays it’s more common to just replace with new.