gr8fulRed

My GS has the timing chain...so don't think that needs changing. From OTHER cars I've maintenanced in the past though...I replaced the tensioner along with the timing belt (on Honda's) and the water pump if needed, just because there was no extra labor....just pay the pump cost.

e-man

So why the heck didn't they at least ask me? What does a tensioner cost? $50, if that?

paul29

1991 LS 400 timing belt service, from the manual >> change at 60,000mi if vehicle is used in police or taxi service with extensive idling. For normal service there is no change interval shown. This vehicle has a non-interference engine.

sam12345

iTrader: (1)

91 ls400 is every 90k and as you said its non interference so it will only leave you stranded if it goes

sam12345

iTrader: (1)

You are asking a bearing spinning faster than engine rpm (because it is smaller than the crank pulley) to last 180k miles without seizing. All the bearings that the belt runs on should be changed. I would still ask the dealer they may have changed it and invoiced it under timing belt. It may never seize but why take the chance on an interference engine

By the way it's tensioner and idler not just tensioner

Sorry you don't need to change tensioner that can be reused it's the tensioner pulley. And only use the oem brand wich is what's in this kit. The whole kit is 141 dollars plus shipping

This link shows what you should change

https://www.rockauto.com/catalog/mor...id=407&jpid=12

paul29

Sam12345 Where did you happen find the 90K interval on the 1991 LS400 timing belt. Is that in the Lexus maintenance schedule for that vehicle?

sam12345

iTrader: (1)

Yes, I own a 1992 ls400

I see what you mean. In schedule B of the owners manual it does not mention it

paul29

Sam12345: I have a 1991 LS 400, also have the owners manual and shop manuals. The A and B schedules just go to 60,000 miles or 72mos and it then says to maintain the same intervals after that. Schedule A "Severe service" shows a timing belt change at 60K. Schedule B "Normal" service just shows a valve clearance check/adj at 60K mi and no timing belt change. I bought the 91 LS new and it has not had the belt changed in 24 years and runs perfectly. I am not disputing what you are saying on the 92 LS just that Lexus does not require a timing belt change in "normal service" for the 1991 model in the OEM Lexus owner and OEM shop manuals that I have.

sam12345

iTrader: (1)

Yes I see that I guess they changed the normal to 90k when they went to interference engines. I had an avalon that did not have an interference engine so I did not change it. At 150k the water pump seized and the timing belt ripped to shreds it even broke the timing belt cover. Of course no engine damage. I would not take that risk on an interference engine. Granted the lexus v8 timing belt is much heftier but I bet if the water pump seizes or one of those bearings it will tear the belt up

sam12345

iTrader: (1)

Share
Water Pump Housing Broke Destroying Timing Belt And Valves - 93 - 05 Lexus GS300 / GS400 / GS430 - Lexus Owners Club (USA & Canada) http://us.lexusownersclub.com/forums...lt-and-valves/

Share
GS400 possible purchase with broken timing belt. Options? - Club Lexus Forums https://www.clublexus.com/forums/gs-...t-options.html

Share
Another Timing belt question - Club Lexus Forums https://www.clublexus.com/forums/ls4...-question.html

Share
Broken Timing Belt Confirmed | IH8MUD Forum http://forum.ih8mud.com/threads/brok...firmed.778650/ (Share from CM Browser)

Share
GS400 Ever seen a timing belt break? - Club Lexus Forums https://www.clublexus.com/forums/mai...elt-break.html (Share from CM Browser)

paul29

I did find out that the early timing belts in the 70>80's were high temperature neoprene which had short lives. Still being produced The LS 400 had a HSN timing belt which is made from Highly Saturated Nitrile rubber and has superior mechanical and chemical resistance properties for long life. Gates timing belts are made of HSN, Dayco uses EPDM in their timing belts and they are also a quality product.

sam12345

iTrader: (1)

My point. And as you can see from the multiple links I posted, it's not the timing belt that fails, it's the water pump and pulleys that make the timing belt fail. So not changing the pulleys and water pump when changing the timing belt is asinine regardless what the dealer says and does. Just as never changing your transmission fluid is asinine.

e-man

So, in reality, what am I supposed to do at this point? I will definitely ask the question, but the invoice is clear -- it reads timing belt $80. There's no way that included any other parts. I just don't understand why a Lexus dealership wouldn't replace the other parts, or at least offer.

sam12345

iTrader: (1)

I would change it at 150k again. My gs400 had 150k when I bought it and the timing belt had never been changed. When I changed it the teeth were starting to crack. As far as the water pump, are you using toyota red coolant? Are you changing the coolant every 5 years? Then it will probably last. The bearings I'm not sure. But if you start hearing whining noises or any such noises that indicate bearing failures then change them. Most likely they will last to 150k. In the end a brand new pulley can fail it's all a gamble. That is one nice thing about non interference engines. But we all like the power.sorry to worry you. Next time you do major service I would read these forums first so you are well educated before going to a mechanic. On the other side, many people only change the water pump every other timing belt change.oh I forgot, you did change the water pump. I think the pulleys probably have a lower failure rate. Keep in mind probability is still on your side, it is just frustrating that it would be 5 extra minutes and 60 more dollars to put new ones in so I have no idea why lexus would not just change them. How much did they charge you?

sam12345

iTrader: (1)

I may have some good news. It seems lexus will cover your car if it fails due to the service being done by them. At least this link insinuates that. So call your dealer and see if they back their work

Share
broken vvti pulley results in timing belt failure / bent valves - Pag
e 2 - Club Lexus Forums https://www.clublexus.com/forums/ls4...-valves-2.html (Share from CM Browser)