Caseoane

Looks mint! Welcome to the forum!

DiggerJim

Couple different things happened. For the belt life (in terms of miles), belt technology has changed in the past 10+ years. Lots more use of synthetic fibers like Aramid (kevlar) so the belts are stronger. They also have better adhesion between the various layers of the belt. All the result of improvements in chemistry and manufacturing.

But...more crap in the air in lots of places that cause aging of rubber, fabric, etc. materials exposed to the atmosphere - especially when further exposed to high temps. The acidic air in many areas causes chemical weakening of the belt. So, that drives a time based renewal recommendation. The belt looks good and hasn't worn from use but is weaker due to the degradation of the materials.

Add a couple of changes to engine technology. Lots of older cars used a timing chain and not a belt. The chains make noise as they wear and give you plenty of warning to get it replaced. The move to belts allowed for quieter operation but belts don't give you an audible warning when they're starting to wear out. Now add in multi-valve cylinders (like 3 or 4 valves vs the old style intake & exhaust valves) and changes in piston head profiles for improved ignition & flame front control, higher compression, etc and now you've got yourself an interference engine where when the timing belt goes the piston in at least one cylinder is going to slam into one or more valves and then the rod goes and you've got cylinder, piston, rod and crank damage.

Not wanting people whining about needing very expensive engine repairs due to delayed replacement of the timing belt it makes sense for manufacturers to recommend conservative change intervals. If the belt could go 150,000 miles it makes sense (for them) to recommend it be replaced before 100K. Almost no chance one will fail prematurely and have them on the hook for an engine. Even within normal manufacturing deviations from spec, a 50% or more buffer between design life and replacement recommendation, a bad belt is still almost certainly replaced before it fails.

Think of it as insurance - replace it well before it fails (for a few hundred $) and save even the small chance of a failure that will cost thousands of $.

Just like airplanes - replace stuff before it breaks and you can keep it running forever.

SlvBullet

iTrader: (8)

Because the belts include rubber compound the manufacturer recommends 7-8 years of life ... They can deteriorate with time. I changed my 2004 at 8 years with about 55k miles. Better safe than sorry.

Bgw70

Thank you all for the reasons why I should change the timing belt based on time and mileage.

Bgw70

The rear speakers are not working. I ordered new foam for the sub, two rear and two door speakers. I installed the new foam on the sub without using a multimeter to ohm out the speaker. MISTAKE! The sub voice coil is open along with the other rear speakers.

Lexus sure did a fantastic job creating a very unique speaker system. Like many others, my choices are, install aftermarket speakers and make them fit the best I can or purchase overpriced ML speakers.

Bgw70

Repaired sub foam...it looks nice but the voice coil is bad. The voice coil is located in the center of the magnet and is the item that pushes and pulls the cone.

Bgw70

Sub location...from the front seat looking aft. the car is very easy to disassemble.

Bgw70

I confirmed the amplifier is good. now I need to locate a replacement subwoofer and two rear speakers. Hopefully I will be able to locate ML speakers that require the foam but have good voice coils. Which means I might save a few dollars.

ShawnOk

iTrader: (1)

If you want a true upgrade for the rear speakers or door speakers, I have a set of JL Audio 6.5" 8Ohm speakers. They will work with the stock system and put no additional drain on the ML amp, therefore keep you out of the threat of destroying the amp. They would require some modification to the OEM stock plates. Just a thought, if you're interested.

Bgw70

Hey Shawn, let me think about your offer and send me the model number and your asking price. Will your speakers fit in place of the "5in" stock Lexus speakers?

Bgw70

Well I opened up the doors to find Sony two-way 6x9 speakers installed. With that said, I am still on the fence on which way to go from here but I am leaning towards an aftermarket install.

BTW, I did not take the door panel completely off because it was difficult to remove from the top. Does it just lift out of the top?

ShawnOk

iTrader: (1)

BGW, I will PM you in a bit with the details on the speakers I have. Here's a link to read up on. If you're running Sony 6x9 in the doors, likelihood is they are 4ohm which is bad for our ML amp. With time lots of owners have their amps burn out, Since we are supposed to run 8ohm, 4ohm causes an increased load on the amp and makes it run hot, therefore more likely to burn out. I try to keep my system at 8ohm as recommended. This JL speakers would need modification but sound amazing. Lots of nice deep bass. I'm not sure how top end you'd like to make your system, but there's a lot of high end systems with people that have modified door panels and the rear seat to make larger speakers fit. How invasive do you want to go?

As for the panel, make sure you've removed all the screws (especially the one under the window switch, under the crescent shaped plastic handle dressing, and the one under the arm rest inside the pocket). Then roll the window down. Trace around the outer edge of the panel with your hand so you're able to pop the plastic retainers out. Then the entire panel should pull up. I always angle the rear part of the panel up and then the front, as if spinning the entire panel counterclockwise. Hopefully this helps.

https://www.clublexus.com/forums/sc4...ubwoofers.html

Harold57

Bgw70, I did a write up on replacing the little triangle weatherstripping on the doors a while back that describes how to remove the panels (post # 37). There are some others out there also. Unfortunately, I didn't include any pictures. However Bob included a couple of attachments on that same thread but on the previous page (post # 19) with diagrams of the door though. Between the description and the diagrams, you should have all you need for a successful removal.

https://www.clublexus.com/forums/sc-...d-noise-3.html

One extra hint , on the clips at the front, if any of the clips have a little circle in the middle, press in at the circle to release the clip first. Otherwise you'll likely be replacing the clips. (They are cheap but difficult to find and describe to the Lexus parts department.)

Bgw70

[QUOTE=mademedoit;8903419]This is the sub I bought a few months ago...http://www.ebay.com/itm/NEW-8-DVC-Subwoofer-Speaker-8-ohm-Woofer-eight-inch-Sub-Dual-Voice-Coil-bass-/181150365903?pt=LH_DefaultDomain_0&hash=item2a2d6738cf
It has a heavier magnet and weighs probliy like one pound more than the factory sub. Puts out a little more bass in the back. You must take the time to solder it in series because its 8 ohm and you want to mimic the factory 16 ohm. Unforchanitly all name brand stuff is 2 or 4 ohms, the positive is that its only $40 for this one. Made in China of course.

Just to be clear and looking at your picture, positive lead (blue) from amp to the speakers right side positive terminal.
Negative lead (black) from amplifier to negative terminal on the left side of speaker.

White wire completes the circuit by going from the negative terminal on the right side of the speaker to the positive terminal on the left side of the speaker.

BTW, a huge thanks for sharing!!! Are you getting more base out of this speaker or from the removal of insulation in the trunk?

Did you need to modify anything in the car to mount this sub?

Bgw70

Great! I just placed an order for the sub. Do you have any info on the rear speakers?