hey so right now on my path to fix my 7 i have found the next three big problems i want to tackle, and i've been doing some research and a lot of reading and i think i know what the problems are and how to fix them, and as the title says and thoughts/help you can give would be tremendously appreciated!!!
problems:
1)oil leak- i think it is coming from my oil level sensor in the oil pan, and a little bit seems to be from the metering oil pump or whatever...the thing is the entire bottom of my car is covered in oil and it seems as though some of it burns off my catalytic so i need this fixed first to prevent any possible fire second to make other work on the car easier and less oily, so i figure replase the line and oil level sensor and do the same with the metering pump
2)spedometer doesnt work-ok well it works at certain speeeds like my speedo likes to **** with me, and im sick of not knowing how fast im going, gotta make sure im going fast enough to get locked up for a couple days, i know there is a speedo cable that conects to the tranny, but how doesit connect and will it do me anygood to try and replace it also how much work is that, and if anyone knows of a thread showing how to do it or anything, thatd be great
3)horrible vibrations-i get vibratrions through my steering wheel and most of the rest of the car and it seems as though it calms down at certain times, haven't really noticed a pattern to the madness but it definetly gets worse and better at times, i think its my wheel bearings, the front ones to be peticular, i bought all the stuff to do it i think...don't know what size cotter pins are needed..any help?also are there any specialty tools needed? i have inner and outer bearings for both sides and grease...is that all i need? should i buy some new wheel bearing seals?

 

As far as the oil leak, if you are saying it is getting on the catalytic converter I would diffenently lead that to the oil metering pump seals. You can buy a rebuild kit from Mazdatrix... fairly cheap and not hard to do. But be very careful when messing with the oil lines, they become bittle after 20 years or rotary heat. For the oil around the level sensor I would spray it clean and monitor it and see if it really is causing a leak. You will be surprised where oil gets and doesnt really have a leak around it.

The Speedometer is done by a cable that runs from the transmission to the back of the cluster. This is another fairly easy job and you can just pick one up from a junk yard. This has two advantages. 1)getting the part at a cheaper price, 2) you can now see how if comes off and not break anything at your expense. You simply take the cluster surrounding off and then remove the cluster itself. There will be 2 main wiring harness pluged into the back of the cluster along with the speedometer cable. Once you tilt the cluster where you can see back there slitly this will make better sense.

your best bet if you think your wheel bearings are bad is to test them...how to do this is drive slowly through a neighborhood with turns and when you make the turn watch and listen to a change in noise or feel while making the turn. The wheel bearing will alter in sound or feel when you apply pressure to it when your in the turn. The wheel bearings have to be pressed in so I would take it to a wheel shop to have that done.