I'm sure there is a very simple answer.

[X53Jay4.8is]

Originally Posted by jopecasa

Maybe your newly acquired X5.....was towing constantly and at short distances.

Normal oil temp was not attained and was pushing stress to the motor....hence failure on the guides.

.......just my opinion.

I think the original posters X5 had a hard 61K miles of use that would equate to to a 130K mile unit that has seen normal maintenance. As long as you run through the X5 and do all of the servicing it will be good for the miles that he wants to explore with his big red rig.

[crystalworks]

Just an anecdote for you regarding guides on the straight sixes. I have an M52 in the garage right now pulled out of a car to swap into one that a buddy overheated and blew the motor on. I pulled the oil pan to do the gasket (because why not while it's on an engine stand) and low and behold; the chain guides had disintegrated and pieces were all over the pan...

It's still on the engine stand waiting for me to find time to do the guides. Engine ran fine BTW. No codes. Not even very noisy really.

[AV8R4AA]

I'm no engineer but a simple sprocket well placed seems like it would
solve these flimsy plastic wagon ruts called guides.
For those of you old enough, remember when the sprocket tip chainsaw invention
came out? Sure was a simple idea that worked wonders.

BMW should have done a better job on this.

[X53Jay4.8is]

Originally Posted by AV8R4AA

I'm no engineer but a simple sprocket well placed seems like it would
solve these flimsy plastic wagon ruts called guides.
For those of you old enough, remember when the sprocket tip chainsaw invention
came out? Sure was a simple idea that worked wonders.

BMW should have done a better job on this.

Greg I know what you are talking about. My first car was a german Capri 1973 with 2600cc V6. Ford originally used a fiber gear in the engine for timing chain quietness and smoothness. Well after 100K the fiber gear would fall apart but the fix was a steel gear that Ford designed and sourced. Once you put the steel gears in the there the engine theoretically would last foreevever (300K + miles). You can definitely have it engineered better than what BMW used but keep in mind the engineers are tasked with "keep cost low and build in some obsolescence so that customers have to return to buying a new vehicle at some point". In today's BMW its like 100-150K because the components that will fail in that time frame will just cost the average customer too much to keep it running and around. Hence time for the new car. By the way this is just not the philosophy of BMW but pretty much all of the automotive manufacturers.

[dannyzabolotny]

Originally Posted by AV8R4AA

I'm no engineer but a simple sprocket well placed seems like it would
solve these flimsy plastic wagon ruts called guides.
For those of you old enough, remember when the sprocket tip chainsaw invention
came out? Sure was a simple idea that worked wonders.

BMW should have done a better job on this.

Funny you mentioned that, the BMW M60 V8 had that exact design!



It used a sprocket instead of a U-guide and a double timing chain. Those M60's lasted damn near forever (if they weren't affected by the infamous Nikasil issue). That's why I tell people to get a 1995 740il if they want a good beater— they're dirt cheap and have a nearly indestructible drivetrain with the M60 and 5HP30.

No idea why BMW abandoned that with the M62, though I think cost-cutting was the main factor, since they brought it back for the more expensive S62.

[X53Jay4.8is]

Cost cutting is forever being applied to the modern day car and its not a new philosophy. Yes the the double timing chain is robust in the M60 V8 engine. BMWs first mas produced V8.