I have stopped checking timing chain stretch on any engine over 250000 miles, the labor/time is identical to replace the chain, the cost of a chain is cheap insurance, and it generally improves performance:

There is only one brand of timing chain to use.
Warning, Danger: Please read this thread FIRST...
Need Automotive Grade Prozac
Need Automotive Grade Prozac = timing chain


OEM: brand IWIS
Timing Chain, With Master Link Double Row - 136 Links
MB# 003 997 62 94

Fastlane: OEM: brand IWIS
http://catalog.peachparts.com/item.wws?sku=W0133-1608200

The best guide rail is SWAG

Fastlane: tensioning guide rail
http://catalog.peachparts.com/item.wws?sku=6150500916

Fastlane: upper guide rail
http://catalog.peachparts.com/item.wws?sku=6150501416

Fastlane: lower outer guide rail
http://catalog.peachparts.com/item.wws?sku=6150521016

Fastlane: lower inner guide rail
http://catalog.peachparts.com/item.wws?sku=6150521116

FYI: Links you may need.

Diesel Timing Chain Link Thread
http://www.peachparts.com/shopforum/diesel-discussion/162071-diesel-timing-chain-thread-post1251434.html

Diesel Injection:
Diesel Injection:

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