T2 Brake master on GTU-S; straight swap?
 

I think the master cylinder on my GTUs is taking a shit. it makes a "clicking" noise as i back off the pedal and there is a slow fluid leak. it seems to be leaking out of the master cylinder and down the front of the brake booster. i think the bore of my master cyl is so shot that the piston is not traveling properly and its binding up as i let off the pedal. that would probably explain the leakage too.

so, i think my stocker is a 7/8" bore, and the T2 is 1/16" larger at 15/16" diameter, right? is it a straight bolt-on procedure and improve my pedal feel/reduce pedal travel?

thanks
chris

sorry off topic but how do you tell that ur car is 1 of 100? I have a 89 gtus and wanna know its number

FYI: Precisely 100 of the GTUs were rumored to have been built in 1990. More than 100 were built and sold in 1989.

close, but not exactly. the story is that they built 1100 in 1989, only sold 1000 of them and had 100 left over in 1990 model year. they couldnt sell the 1989-built cars in 1990 as 1989 model units, so they had to change the year code in the VIN's. before my car was shipped from japan, mazda restamped the firewall vin and changed the dash vin and door jamb sticker. i ran a car fax on the firewall vin using the number that was crossed out and showed up as an 1989 model year with no history. i ran another carfax w/ the same VIN but using the number that mazda had re-inserted, it showed up as the same car except a 1990 model year; which matched the dash and door jamb vin's.

oh and as far as finding out the actual production sequence number, i havent found a way. i called the original dealer that my car was bought from as well as Mazda of America and they couldnt tell me anything from the VIN. they said there wasnt a way to find out the sequence since they all rolled off one assembly line and no one was keeping track back then... or something like that.

:icon_tup: Thanks for the info flubyux2, I had never heard that before. I find it interesting that Mazda went to all that trouble in restamping the VIN numbers.

I'm curious though, the unsold '91 RX-7s were sold well into 1992 until the 3rd generation RX-7 debuted. What was the reason for Mazda being unable to simply sell the left-over '89 GTUs(s) into 1990 (as '89 models)?

I love the GTUs.....anyway back to the question. The GTUs has the same suspension and braking system as the TurboII so my guess would be that they are Identical.

I had a creaking/clicking noise coming from the front calipers on my four pots.

I rebuilt the calipers and it went away. You sure its not coming from the calipers?

James

Maybe the 1990 GTUs was supposed to be a limited offering for that model year? i think at this point, we can only speculate unless we find someone who had inside information back then. i have yet to meet another person with a 1990 GTUs. everyone i hear from or talk to has an 1989, so obviously their VIN's arent like mine.

btw, i just finagled a one-of-a-kind deal on some brake pads between one auto zone and 2 discount auto part stores. after i put the new pads on and bled all 4 corners w/ a pint of fluid, the "clicking" went away. i think my noise was from the driverside pad back-plate binding on the pins. the outboard pad was worn unevenly and down to the metal back plate. fortunately, i had only put about 14 miles on the car w/ the backplate exposed to the rotor. after i bled the brakes, i had about 16oz of BLACK burned DOT4 fluid. the rear calipers werent nearly as bad, tea-colored. i bedded in the new pads, 6x 30-5mph stops @ half pedal, 6x50-5mph stops @ half pedal and 2x70-5mph stops @ full pedal... the pads were up to temp before the last 3 stops. they feel great considering they are budget semi-metallics.

i had my OLD pads warrantied out and got FULL credit on them and used it towards new NGK plugs and a can of brake cleaner. LOL ;)