acceleration flat spot
Driving the wheels offer
Joined: Sep 2011
Posts: 1,056
Likes: 188
From: Maine USA
last time i drove my truck - no flat spot - but i haven't put gas in it for a few months
wouldn't be surprised if we are getting 10% ethanol and 20% other in our gas these days - the way things are going ...
wouldn't be surprised if we are getting 10% ethanol and 20% other in our gas these days - the way things are going ...
Thread Starter
5 Year Member
Joined: Aug 2013
Posts: 100
Likes: 11
From: Maine
It might be bad gas or the high humidity we've been experiencing. Thanks for the suggestions
Thread Starter
5 Year Member
Joined: Aug 2013
Posts: 100
Likes: 11
From: Maine
Senior Member
Joined: Oct 2018
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From: Maysville KY
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Joined: Jul 2015
Posts: 3,627
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From: Michigan
3,500 means nothing with a manual. Does it happen at 3,500 in every gear or just the higher gears, 3rd and 4th? I would expect what you describe in overdrive 5th. The truck M5R2 has compromised gearing for towing and load. What you describe seems typical. Try towing something and see if you get a slow but steady acceleration. If not, then you might have a real problem. If you don't like what you have, you can re-gear the transmission to suit you. You can also get the PCM re-tuned.
I've had 3 or 4 M5R2's and they all ran like what you describe. Your other option is put in an automatic.
I've had 3 or 4 M5R2's and they all ran like what you describe. Your other option is put in an automatic.
Last edited by River1; Aug 11, 2020 at 09:25 PM.
Thread Starter
5 Year Member
Joined: Aug 2013
Posts: 100
Likes: 11
From: Maine
3,500 means nothing with a manual. Does it happen at 3,500 in every gear or just the higher gears, 3rd and 4th? I would expect what you describe in overdrive 5th. The truck M5R2 has compromised gearing for towing and load. What you describe seems typical. Try towing something and see if you get a slow but steady acceleration. If not, then you might have a real problem. If you don't like what you have, you can re-gear the transmission to suit you. You can also get the PCM re-tuned.
I've had 3 or 4 M5R2's and they all ran like what you describe. Your other option is put in an automatic.
I've had 3 or 4 M5R2's and they all ran like what you describe. Your other option is put in an automatic.
Senior Member
Joined: Dec 2015
Posts: 23,191
Likes: 8,619
From: Utah
All we are getting told is that this is sluggish. Nothing abut condition of the motor, etc. Please tell us when your last tune up was. What did it consist of, including the brand of the parts used (yes it matters)? Any exhaust work done lately? If you want help, you need to be more descriptive.
Senior Member
Joined: Jul 2015
Posts: 3,627
Likes: 795
From: Michigan
Good luck. Give yourself enough time and you'll read what you want to read.
Thread Starter
5 Year Member
Joined: Aug 2013
Posts: 100
Likes: 11
From: Maine
All we are getting told is that this is sluggish. Nothing abut condition of the motor, etc. Please tell us when your last tune up was. What did it consist of, including the brand of the parts used (yes it matters)? Any exhaust work done lately? If you want help, you need to be more descriptive.
Last edited by dhansen; Aug 13, 2020 at 09:39 AM. Reason: added another part
Thread Starter
5 Year Member
Joined: Aug 2013
Posts: 100
Likes: 11
From: Maine
I'm sure 2 years ago or 20 years ago your truck has never had bad gas or been in this high of humidity either. Problem is, I've been to Maine and know that isn't true about humidity. I also know most of Maine lives at darn near sea level and your air density is about as good as it gets. As vehicles age they get less efficient so put new rings in and get your block honed and have your cylinder heads rebuilt and I'm sure you can relive 2 years ago. Or like I said, tow something and see what happens.
Good luck. Give yourself enough time and you'll read what you want to read.
Good luck. Give yourself enough time and you'll read what you want to read.