View Single Post
  #6  
Unread 05-05-2013, 08:19 AM
Smithers's Avatar
Smithers Smithers is offline
Admin
 
Join Date: Feb 2004
Location: San Luis Obispo, CA
Posts: 3,238
Send a message via AIM to Smithers Send a message via Skype™ to Smithers
Default

Another "con" with the 1UZ in an offroad use environment is that the engine wasn't meant for abuse in front of a manual transmission. Timing belts are known to skip a tooth from the harsh on and off throttle transitions in mud and playing around on the street. I don't think this is a problem for off-road use in general since the traction is only super sticky in the deep mud and on the street with grippy tires. Usually off-road the traction isn't that great and there is a lot of wheel spin so it's not stressful. But when you add a whole lot of traction then the belts are under much more stress and tend to slip under higher loads.

I've personally thrown my belt off a tooth during an insane burnout, pedal-to-the-floor throttle while popping the clutch. Then the other week I was simply doing some high rpm accelerating because it's a shame not to run these engines above 7,000 rpm every now and then. I think this led to a timing belt slip on the 1UZ because while I was driving later on I noticed something wasn't right. I drove it home and decided to investigate at another time. Sure enough it was the dreaded belt slip. I think this was because of a failing after market tensioner that I installed brand new when I built the engine. ONLY USE STOCK OEM TIMING BELT TENSIONERS on Lexus/ Toyota engines. That is if you are going to use your engine under higher loads than normal.
Reply With Quote