4.6is just hit 100k miles, what service should I do?

[rmani]

I am planning to do another oil change, coolant flush, power steering fluid, along with differential fluids. Should I also do a tune up?

I'm still out on the transmission fluid, some say to flush it, others say not to. What about just adding some new fluid but not actually flushing the old fluid out?

[c4racer]

Originally Posted by rmani

I am planning to do another oil change, coolant flush, power steering fluid, along with differential fluids. Should I also do a tune up?

I'm still out on the transmission fluid, some say to flush it, others say not to. What about just adding some new fluid but not actually flushing the old fluid out?

I am on the fence on that too and currently at 105K. as a compramise I may just do a drain and refill without doing a pan drop. But then that leaves the filter in there. I dunno - I have heard many sources say that if you didn't change it by 60K you are better off leaving it alone. Seems wrong, but who knows - there are 200K mile BMW trannys on the original fluid, so who is to say.... Could go either way on this one...

You should change the spark plugs, and if you have not replaced the valve covers good chance you will find some oil in the galley where the plugs sit and you will need to change those.

You should have a good look at the cooling system if it is all original. On mine the water pump and expansion tank was replaced at 80K, but is still on original radiator and hoses. I will replace all the lines, thermostat and radiator sometime before 120K miles as preventative.

If serpentine belts have not been changed, do that - way overdue.

fuel pump is not a bad idea. I plan to do that soon. Flushing brake fluid and PS fluid also not a bad idea. I will do my brake fluid at the next brake job.