question about brakes

Messages
220
Location
Mass.
Good morning! i have a 2008 Cadillac DTS with 33,000 miles. will do the brakes. i know 2 good mechanics. one said to replace the pads and rotors. the other said rotors are ok, will just do pads. ideas? explain to me? best bob and THANKS!!!!
 
Messages
25,973
Location
Upstate NY
The one who said pads only, how long did he spend looking at the rotors? The rotor needs to have two parallel surfaces. Each surface needs to be flat without major rust. It needs to be checked with a vernier caliper which has wide jaws. Assume pads and rotors, but maybe you will get lucky on the rotors. The rotors need to be roughed up a bit when the new pads are installed.
 
Messages
1,344
Location
Clinton Twp. MI
Idealy you always replace pads and rotors, or machine the rotors for a new surface if there condition allows. This is how you restore 100% brake efficiency. Many times if the rotors have been inspected and measured only pad replacement is done.This is personal preference or to simply save money, It will not give you like new performance but is usually acceptable.
 

Robertslowpoke

Thread starter
Messages
220
Location
Mass.
thanks! i really take care of this car, want it to last WAY beyond the car loan!! i did new tires yesterday, original michelin. changed trans fluid, radiator, brake, steer fluid, tons of oil changes and oil analysis. sounds like i must specify new rotors and pad. best bob keep the ideas coming!!!! bob
 
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2,695
Location
Easton, PA
if the pads haven't been run down far enough to groove the rotors, you can probably keep using them w/ new pads. they just need to be scuffed up to remove the glaze.
 
Messages
25,973
Location
Upstate NY
As an aside, how was the trans fluid changed? Get an inline filter for the ATF if you want the transmission to last for a long time. A Magnefine is $20.
 

Robertslowpoke

Thread starter
Messages
220
Location
Mass.
hi Donald! my friend removed the pan, drained whatever fluid came out. (not all, I guess) this was around 30,000 miles. he changed the filter and replaced fluid with the proper dexron fluid for cadillac. there were particles in the filter screen, he showed me. where do you put the inline filter? how to do it? how often would YOU change trans. fluid? i want to get 150,000 miles from this car. i detail and wax very often. lots of salt and snow here in winter. you know, spending $100 a year on trans. fluid is cheaper than replacing a caddy!! ha! when car loan is done, i need this car to last!!!! thank you bob
 
Messages
14,505
Location
Top of Virginia
That 4T80-E transaxle in your Cadillac will last forever, no matter what you do. I've owned two FWD Northstar Cadillacs...these transaxles are bulletproof. If you change the fluid every 30k miles, your transaxle will probably outlast the engine.
 

Robertslowpoke

Thread starter
Messages
220
Location
Mass.
thanks Jason!! that is why i ask questions here!! you know that it is a 4T80-E!! ha!! I just know to drive it! easy enough for me to change fluid every 20,000, then i should be ahead of the game!! by the way, how did you like your Caddies? i love mine!! faster than you would think for a 4000 pound car!!!!!! thanks bob
 
Messages
14,505
Location
Top of Virginia
I had a '97 SLS that was fantastic. Mom bought it with 39,000 miles on it, then I bought it from her at somewhere around 80,000 miles, then I sold it to my brother at somewhere around 160,000 miles. VERY few issues with that car. I had a '01 STS that was less than good. I liked the car itself okay, but it wasn't all that reliable and didn't drive very organic-like. I should have kept the '97. Live and learn I guess.
 
Messages
4,998
Location
Milwaukee, WI
Assuming the car winters in Mass, I'd replace the rotors too. They might be fine now, the question is if they will go another 30 or 40,000 miles without developing any "warp". FWIW, though, rotors for either of our cars are under 100 a pair and that might not be the case with a nice Caddy. If you wanted to save some cash, you could certainly keep the rears which almost never affect wobble.
 

Robertslowpoke

Thread starter
Messages
220
Location
Mass.
thanks bepperb!! my friend, a mechanic was doing spark plugs, etc on my 2002 lexus es300, which already had the brakes replaced. he did not like the front rotors, pitted, rusted, etc, and so he did the front brakes. the car does drive daily in winter, i might as well do the rotors!! thanks!! new rotors every 30,000 miles seems reasonable to me! want this car to go forever. do you think it is true, that the front 2 brakes do most of the stopping effort? bob
 
Messages
25,973
Location
Upstate NY
Others seem to have more info on your specific transmission. Just be aware that dropping the pan normally changes only 1/3 of the total ATF capacity. The Amsoil website will tell you exactly how much. Your mechanic should be able to do a DIY flush. Its pretty easy and needs no machine, and does as good a job as a machine. The inline Magnefine filter goes on the return line from the cooler to the transmission. Its a 10 minute job if its rubber hose and a little more if its metal. Basically one just splices the filer in. It filters down to 30 microns. The felt filter you probably have filters down to small pebble size. Also you might consider having your mechanic install a drain plug in the transmission pan if it does not have one. If you have a Magnefine installed you should never again have to drop the pan, assuming you do reasonable maintenance. The Magnefine does need to be changed every 30K, but that takes 5 minutes and you then get to unscrew it and see how much crud it caught (you will ponder over that for at least 30 minutes, and draw all sorts of conclusions). Good luck.
 
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3,431
Location
USA
Originally Posted By: Robertslowpoke
sounds like i must specify new rotors and pad.
Not necessarily the case. You didn't say if either mechanic actually measured the rotors. It could be that they have enough material to machine and one of the mechanics just wants to sell you pads and rotors. I'm not saying that's the case, but at this point you don't seem to really know if it needs rotors or not. However, sometimes it's not worth it to even try to machine the rotors. The vanes in the rotors of my Hyundai were so rusted I decided I would just replace them rather than have them machined.
 
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Messages
25,973
Location
Upstate NY
Its one thing if a shadetree mechanic pulls the rotors and brings them to a place to have them turned. Its another thing if your mechanic either turns them himself (herself) or sends them out. Given the per hour rate for a mechanic (and he does not want to tie up a lift) I cannot see it ever being worth it for a mechanic to do anything but slap on new rotors. And turned rotors are more likely to warp than new. Not saying them will, but a higher probability turned ones will vs new. The NAPA place says they hardly do any these days. Thus the above is true for your garden variety rotors. If you have super premium ones, then things may be different.
 
Messages
19,479
Location
Chicago Area
If a shop has a machine to cut rotors, they will use it. Often, a tech can go to another job while waiting for parts or cutting rotors. You do realize that waiting for parts takes longer than cutting them, don't you? So which is the better use of time?
 
Messages
25,973
Location
Upstate NY
Originally Posted By: mechtech2
If a shop has a machine to cut rotors, they will use it. Often, a tech can go to another job while waiting for parts or cutting rotors. You do realize that waiting for parts takes longer than cutting them, don't you? So which is the better use of time?
I'd gets pads and rotors from RockAuto and bring them with the car. That way he can choose the quality level of the parts.
 
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