which tuner is best for Cummins engines?
#11
04-04-2014, 01:08 PM
he's not running 1000hp...
stock trans/gears/xfer case are fine.
I'm running nearly 600hp/1300lbs/ft at the rears on stock 6-spd trans, stock transfer case, stock rear end, stock drivelines, stock u-joints, etc...
My clutch however is a south bend 3600# double disc with upgraded clutch hydraulics.
I also have trans cool PTO coolers, and a temp probe in one of the coolers to monitor trans temp. overkill for just a smarty as you won't reach over 500hp on stock injectors and turbo..
Just go easy on 6th gear until you are over 2000rpm and you won't have a problem.
stock trans/gears/xfer case are fine.
I'm running nearly 600hp/1300lbs/ft at the rears on stock 6-spd trans, stock transfer case, stock rear end, stock drivelines, stock u-joints, etc...
My clutch however is a south bend 3600# double disc with upgraded clutch hydraulics.
I also have trans cool PTO coolers, and a temp probe in one of the coolers to monitor trans temp. overkill for just a smarty as you won't reach over 500hp on stock injectors and turbo..
Just go easy on 6th gear until you are over 2000rpm and you won't have a problem.
#12
04-14-2014, 08:23 AM
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Thanks for the advice jigabop. Why take it easy on 6th under 2000rpm? I only ask cause at 65mph in cruise my rpms are 1800 to 1900 at 70mph its about 2050. This is the way the truck has always been so just wondering what precautions I should take if any. I figure in the next 30 to 40K miles I will be due a replacement clutch so I will upgrade at that time to a performance clutch.
#13
04-14-2014, 05:43 PM
6th gear is the weakest link in the 6-spd.
I'm on my second 6-spd lol. first was the small input shaft model that was a bit weaker than the later versions which my current trans is a later version.
previous trans I ripped all of the teeth off of 6th gear while going up a 6% grade rolling 50-55mph in 6th with no load in or behind the truck. I put the skinny pedal to the floor and boost jumped very quickly and BANG! I'm free revving and grinding. 6th was gone and the same gear on the main shaft that engages 6th also engages 5th on the secondary, so lost both 5th and 6th and had to grind it into 4th to keep going till I got to the top of the grade because there was absolutely nowhere to pull off the highway till the top. jersey barrier on the left and guard rail on the right, no shoulder.
pulled off at the summit to check and make sure I didn't punch a hole in the trans case or anything, and heard the grinding at idle inside the trans. still had reverse and 1st-4th gears. so got it home in 4th cruising slow. had to replace the trans since the 5600s aren't serviceable without special tools/equipment.
so as a precaution I take it easy in 6th till I'm already well into boost before I hammer down and I have make my tuning less aggressive. still just as powerful, but doesn't slam into the power anymore...more rolls into the power now.
I'm on my second 6-spd lol. first was the small input shaft model that was a bit weaker than the later versions which my current trans is a later version.
previous trans I ripped all of the teeth off of 6th gear while going up a 6% grade rolling 50-55mph in 6th with no load in or behind the truck. I put the skinny pedal to the floor and boost jumped very quickly and BANG! I'm free revving and grinding. 6th was gone and the same gear on the main shaft that engages 6th also engages 5th on the secondary, so lost both 5th and 6th and had to grind it into 4th to keep going till I got to the top of the grade because there was absolutely nowhere to pull off the highway till the top. jersey barrier on the left and guard rail on the right, no shoulder.
pulled off at the summit to check and make sure I didn't punch a hole in the trans case or anything, and heard the grinding at idle inside the trans. still had reverse and 1st-4th gears. so got it home in 4th cruising slow. had to replace the trans since the 5600s aren't serviceable without special tools/equipment.
so as a precaution I take it easy in 6th till I'm already well into boost before I hammer down and I have make my tuning less aggressive. still just as powerful, but doesn't slam into the power anymore...more rolls into the power now.