Replacing Hoses, Belt And Other Rubber

GKLCPA · July 1, 2011

Last time I had my car into the mechanic, I was told that my hoses are dry rotting and require change. It occurs to me that this would be a good time to deal with anything that's rubber given that my 1996 LS is nearly 16 years old. Here are my questions:

1) What hoses are good candidates to replace?

2) Does it make sense to replace all drive belts?

3) What other rubber components should I consider changing?

Thanks in advance for your assistance.

steve2006 · July 3, 2011

I have 1994 import LS400 and at 17 years old my hoses are in perfect condition and serviceable so why your mechanic has suggested changing them all I don't know,are they collapsed,leaking or falling to pieces?

There are a lot of rubber components on and around the engine and to replace them all would be time consuming ( so expensive) and expensive to buy in the first place.

Check the main coolant hoses yourself are they showing and signs of deterioration for example cracks in the rubber?

Drive belts should be replaced at the recommended service intervals there are only 2 the serpentine belt and the timing belt of the 2 the timing belt is the most important as if it breaks it's basically new engine time.

Other rubber components that do wear out are the motor and transmission mounts but again a visual inspection should determine if these are good or bad plus you would have noticed excesive engine movement should they have gone.

It sounds like your mechanic is asking you to have unneccesary work done if in doubt seek a 2nd opinion.

SRK · July 3, 2011

I still service my 92 LS now that a customer has purchased it. The hoses are in perfect condition. The serpentine belt has been replaced once, the timing belt twice and the car has 215,000 km on it. I don't know what standards Lexus used for the hoses, but they obviously exceed every other manufacturers. So I'd agree your mechanic is sniffing around for work. It's clear that one should only use factory parts when replacing these items when needed, and the price is high. Removing a Lexus hose and installing a Gates or other aftermarket part would be foolish.

If it ain't broke, don't fix it.

GKLCPA · July 3, 2011

I still service my 92 LS now that a customer has purchased it. The hoses are in perfect condition. The serpentine belt has been replaced once, the timing belt twice and the car has 215,000 km on it. I don't know what standards Lexus used for the hoses, but they obviously exceed every other manufacturers. So I'd agree your mechanic is sniffing around for work. It's clear that one should only use factory parts when replacing these items when needed, and the price is high. Removing a Lexus hose and installing a Gates or other aftermarket part would be foolish.

If it ain't broke, don't fix it.

The timing belt service has been done twice. Both mechanics were referring to the cooling system hoses. Actually, I've not taken a look myself and that's what I should do before doing anything. I'm getting ready to take a long trip and just wanted to make sure things were on order prior to doing that.

landar · July 4, 2011

The timing belt service has been done twice. Both mechanics were referring to the cooling system hoses. Actually, I've not taken a look myself and that's what I should do before doing anything. I'm getting ready to take a long trip and just wanted to make sure things were on order prior to doing that.

If you have two mechanics telling you the coolant hoses are on the way out, then I would pay attention. If you feel competent to inspect and access the hose condition, you can decide. If not, go with the mechanics recommendation. These OEM hoses are very durable so if they do not appear rotted or cracked they are probably ok. Be aware that you cannot always tell what is going on inside the hose just by examining the outside. IMO, it would not be unreasonable to replace them after 16 years. The serpentine belt is a very easy item to replace yourself.

GKLCPA · July 4, 2011

The timing belt service has been done twice. Both mechanics were referring to the cooling system hoses. Actually, I've not taken a look myself and that's what I should do before doing anything. I'm getting ready to take a long trip and just wanted to make sure things were on order prior to doing that.

If you have two mechanics telling you the coolant hoses are on the way out, then I would pay attention. If you feel competent to inspect and access the hose condition, you can decide. If not, go with the mechanics recommendation. These OEM hoses are very durable so if they do not appear rotted or cracked they are probably ok. Be aware that you cannot always tell what is going on inside the hose just by examining the outside. IMO, it would not be unreasonable to replace them after 16 years. The serpentine belt is a very easy item to replace yourself.

I have a 25 year old BMW that's my daily driver now and one of the things that's very helpful with that car is a Bentley manual that explains pretty much everything about the car. Is there something similar for the LS? That'd be helpful for the serpentine belt change out.

steve2006 · July 4, 2011

A bit of searching can reveal loads of informations for the Lexus LS400,below is a link detailing the replacement of the serpentine belt and this resource has lots of other tutorials.

http://www.lexls.com/tutorials/maintenance/drivebelt.html

The original Lexus service manuals sometimes appear on ebay or there are some good CD ROM versions around for a few $$$.