|
|
|
My daughters and I are still driving the 940s. I ran into something this morning I didn't know.
I brought my daughter's 1995 940 in for replacement of the front rotors and pads (which I had new but they were separate pieces) and a front end alignment. I have done many myself (except for the alignment) but old age is creeping up!
The shop found that the 940 had one piece rotors with the hubs and toner ring pressed in. They didn't want to press out the old parts for fear of breaking the hub or rotor.
Does anyone have the part number of the one piece rotor with hub and toner ring pressed in?
Thanks once again!
JD620
--
Mine:3-940s running; 1-740, 2-940 parts; dtrs:4-940s running
|
|
-
|
|
|
Dear jd620,
Hope you're well and stay so. I have never heard of - or seen - for a 940, a one-piece brake rotor and hub unit.
According to Volvo VADIS - a superseded dealer parts and service database - the one-part design (rotor and hub unit) ended with the 1987 model year, i.e., long before the 940 was produced.
For 740s produced in and after 1988 - at least for North American markets - the hub and the rotor are separate parts, i.e., they may be replaced independent of each other.
Your mechanic - perhaps unfamiliar with the 940 - seems to mistake a rotor corrosion-bonded to the hub, for a factory-supplied unit. I do not believe that Volvo ever sold a single hub-and-rotor unit for the 940. The reason: front rotors need to be changed periodically. Hubs can last for 200,000 miles, absent collision/road hazard damage.
I'd squirt PB Blaster, Kroil, or a similar penetrating oil, at the base of each of the studs, on which the wheel is mounted, where the studs protrude through the rotor's outer surface.
With time - and gentle tapping on the edge of the to-be-replaced rotor - the penetrating oil will permeate micro-channels in the corrosion. This will weaken the corrosion bond. The rotor will then come free from the hub.
The hub's face should then be cleaned of corrosion with a rotary wire brush, on an air-powered grinder. Once all corrosion has been removed from the hub, a thin, even coat of nickel anti-seize should be applied to the hub's face. That will keep the new rotor from bonding to the hub.
Hope this helps.
Yours faithfully,
Spook
|
|
-
|
|
|
Thanks Spook for the reply.
I hadn't heard of a a one-piece brake rotor and hub unit either but I haven't had 1995 940 front brakes apart before.
Have you heard of AM-Autoparts, Optimal or SKF bearings? They are inexpensive but I don't want a replacement that doesn't last 20K or 30K miles (car has 200K+ miles on it).
I appreciate the reply.
--
Mine:3-940s running; 1-740, 2-940 parts; dtrs:4-940s running
|
|
-
|
|
|
Dear jd620,
Hope you're well and stay so. You're welcome! I'm pretty sure that SKF - a Sweden-based bearing-maker - supplied hubs to Volvo, when 940s were made.
While the hub and rotor are separate items, the hub and its bearings are replaced as a unit. The Volvo part number for a hub is 271644.
The tone (toothed) ring - Volvo #6819759 - can be separated from the hub if: (a) it is not corrosion-bonded and (b) care is taken to keep the bearings in place, during tone ring removal. Some hubs are supplied with the tone ring installed. A replacement tone ring costs about $85 at a U.S.-based Volvo dealer.
Hope this helps.
Yours faithfully,
Spook
|
|
-
|
|
|
skf are oem hubs and you can buy directly from them. I got a good price on sale last fall. I got Zimmermann coated rotors and will do this job when the weather warms up.
According to ATE german tech support: they insist that only a light coat of oil is to be applied to the mating surface of the rotor and the hub.
I felt like skpook that a light film of anti-seez is appropriate, but no, according to the experts. You can check ate and zimmermann tech websites,
they are adamant about this.
There's special wire brush tools to clean the old hub if you reuse it. the hub has to be pristine to avoid runout. See the ate and zimmermann websites for more details, including a break in procedure for new rotors and pads.
avoid cheap chinese hubs and rotors like the plague, they are junk.
good luck, Bill
|
|
-
|
|
|
Dear B.B.,
Hope you're well and stay so. I've no doubt you accurately report advice from ATE tech support. But I fear "a light coat of oil" will not last. Brake rotors get warm often and occasionally get hot. Nickel-based anti-seize is good to 2,400°F.
The ATE technicians advise against anti-seize, because they fear - correctly - that most will apply far too much anti-seize.
A thick layer will surely prevent the rotor from mating perfectly with the hub's face. No good comes from that. But an even and very thin coating of anti-seize, carefully applied, should not cause such misalignment.
Stay well!!
Yours faithfully,
Spook
|
|
-
|
|
|
hi spook,
here's the install directions included with coat-z rotors
coat-z looks like a fine zinc coating
https://www.otto-zimmermann.de/en/service/downloads/
Manual Brake Discs and Drums and Sport Brake Discs
974_1000_5_montage_2spr.pdf
check the download section for a variety of technical articles about brakes.
zimmermann did not respond to multiple e-mails.
ate, however, was very good, and their tech support rep Markus Fischer agrees with zimmermann: here's his remarks from 3 e-mails, since i also felt anti-seez was a good idea.
1.
"ATE recommends no grease between rotor to wheel bearing/hub flange.
After cleaning the wheel hub, only a light oil should be applied to the hub and wiped off with a clean cloth."
2.
"use only a little light oil on the wheel hubs, to prolong the corrosions process a little.
Normally nothing is applied to the wheel hubs after cleaning.
Because the wheel hub must completely flat.
There is no special oil for this process.
If you were to apply grease on the wheel hubs, there would be a risk that the brake disc would not lie flat on the wheel hub.
And vibration could occur."
3.
... "Please, do not use any grease.
Rust will still occur on the wheel hubs and brake discs.
The temperature of the brake disc varies from car to car.
An average value under very high loads is perhaps 500 degrees ( Celcius)."
============
the skf hub for the 940 is:
https://vehicleaftermarket.skf.com/us/en/products/BR930056K
sourcing hubs is an adventure. since many companies catalog the hub
beck arnley and others rebrand other companies hubs.
what you don't want is a rebranded chinese hub.
genuine skf or fag to be preferred.
look carefully at skf's catalog and they sell different 940 hubs to different world markets.
https://www.yoyopart.com/oem/12358613/chicagorawhide-br930056k.html#interchange
DT Components 513170 Axle Bearing and Hub Assembly
Precision Seals & Bearings 513170 Axle Bearing and Hub Assembly
BECK/ARNLEY 051-6082 Wheel Bearing and Hub Assembly
SNR R165.14 Wheel Hub Bearing
FAG 713 6600 20 Wheel Hub Bearing
FAG FW9170 Wheel Hub Bearing
TIMKEN HA590056K Wheel Bearing and Hub Assembly
SKF BAFB246746AAW2 Axle Bearing and Hub Assembly
SKF BAFB246746AAWB Axle Bearing and Hub Assembly
SKF BR930056K Axle Bearing and Hub Assembly
SKF VKBA1435 Wheel Hub Bearing
FEDERAL MOGUL 513170 Axle Bearing and Hub Assembly
VOLVO 271 644 Wheel Hub Bearing
VOLVO 271644-7 Wheel Hub Bearing
VOLVO 3516037 Wheel Hub Bearing
VOLVO 3516037-3 Wheel Hub Bearing
Application of CHICAGO RAWHIDE BR930056K
Make Modle Engine CC KW cylinder Type Year
VOLVO 740 All Axle Bearing and Hub Assembly - FRONT 92-89
VOLVO 760 All Axle Bearing and Hub Assembly - FRONT 90-89
VOLVO 780 All Axle Bearing and Hub Assembly - FRONT 91-89
VOLVO 940 All Axle Bearing and Hub Assembly - FRONT 95-91
VOLVO 960 All Axle Bearing and Hub Assembly - FRONT 94-92
========
skf is out of stock and no sale going on
rockauto has a single hub in stock at a very low price, is it genuine skf?
https://www.summitracing.com/parts/skf-br930056k
|
|
-
|
|
|
Dear B.B.,
Hope you're well and stay so. I didn't doubt that you accurately represented the views of the ATE tech support folks, with whom you spoke!
They are properly concerned that the rotor not be mis-aligned relative to the hub, due to the application of any anti-corrosive material. "Thin" oil will "self-level" - any excess will quickly drain away or be squeezed-out when the lug nuts are tightened. An uneven coating of any other anti-corrosion material could well cause a mis-alignment between the rotor and the hub.
I accept those statements as true and correct. My point is simple: a thin, even layer of nickel-anti-seize will not give rise to a rotor-hub misalignment, but will prevent formation of a corrosion bond between the rotor and the hub.
As to the various hubs that SKF makes/markets for 940s, I limited my comments to what I see in Volvo VADIS for vehicles sold in North American markets.
Hope this helps. Stay well!!!
Yours faithfully,
Spook
|
|
|
|
|
