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Discussion Starter · #1 ·
Also...I read that lifting a diesel is bad because of cooling issues. Plus I heard bigger tires really screw up trannys on a diesel because of all the torque. And the mini computers Example: (Bully Dog). that you buy...people say it makes the tranny slip very easily. And one more thing....an aftermarket pipe..people say it makes black smoke come out...which means waste of fuel..is this true? And whats a Cat?
 

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Body lifts on a diesel can be bad because of cooling issues. There are many people that have suspension lifts with no issues. Don't worry about bigger tires, most people put them on and have no issues. There is a TSB out for having bigger tires with the allison, I feel it is BS because the hummer h1 comes with 37" tires on it. Aftermarket pipes do not cause black smoke. People running crazy tunes do. If you have good programming, you won't see very much black smoke if at all any. The rule of thumb with the programmers is to keep it under 100hp and drive sensibly to not roast the tranny. The tranny will save itself before too much damage is done by going into limp mode.(failsafe) Lastly, a cat is the catalatic converter (sp?)...emissions crap that restricts the exhaust and raises exhaust gas temps (EGTs).
 

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Body lifts on a diesel can be bad because of cooling issues. There are many people that have suspension lifts with no issues. Don't worry about bigger tires, most people put them on and have no issues. There is a TSB out for having bigger tires with the allison, I feel it is BS because the hummer h1 comes with 37" tires on it. Aftermarket pipes do not cause black smoke. People running crazy tunes do. If you have good programming, you won't see very much black smoke if at all any. The rule of thumb with the programmers is to keep it under 100hp and drive sensibly to not roast the tranny. The tranny will save itself before too much damage is done by going into limp mode.(failsafe) Lastly, a cat is the catalatic converter (sp?)...emissions crap that restricts the exhaust and raises exhaust gas temps (EGTs).
Ditto,couldn't have said it better myself..:drink
 

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Discussion Starter · #4 ·
Thanx...this helps me alot with what I want to do. Now my only question is...did you guys take your catalatic converter off? Or do you still have yours? Or do you have to replace the whole exhaust to get if off? What are the benefits? Added HP maybe?
 

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Well, my truck never came with one...so, I was lucky. Some people buy a cat-back system and buy the front pipe (the pipe where the cat is) so that they can change it out if they have to do emissions inspection or go to the dealer. Another option would be to gut the cat and put the pipe back up. The "off road" systems (comes with the pipe that replaces the cat) are a little cheaper, but you can't just thow the cat back in if you ever needed to.
 

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taking it off will add a little more hp and lower EGTs a bit. like "ob_1jr" said, you could go with a cat back and front pipe, dont have to change the whole exhuast.
 
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