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Towing issues between 3rd and 4th gear.

2K views 20 replies 5 participants last post by  Dugan1 
#1 ·
Ive been towing multiple things lately, and realized that when shifting from 3rd at around 2500-2700 to 4th, the truck falls completely on its face and bogs all the way up 4th gear, sending my EGTS into the roof, 1000-1200 degrees.

Is this normal for these trucks? Ive never had issues with towing in any of my power strokes like this, let alone this high of EGTs.

I did a hill in Lancaster, PA not too long ago while towing, i was in 3rd at 2700rpm just trying to get up it, there was no way i was hitting 4th.

I also discovered my fuel pressure is lower than specified, 15 at idle 20 while driving. Could this cause an issue with power?

I just cleaned my prefilter and put a new fuel filter on. Time for a OFV?

Tortek or LarryBs if that is what i need?
 
#2 ·
The 3-4 jump in these trucks isn't the greatest. I'll run mine right up to 3100 in 3rd if I'm towing a heavy load. 1000-1200 EGT isn't that hot. As long as you don't go over 1250 for an extended period you're fine. Your fuel pressure is low and could be contributing to some of your issue. Try replacing the OFV or at least stretch the spring out and see what that does for you. Have you done any other mods to the engine at all? In bone stock trim, these trucks are not land rockets by any stretch of the imagination...
 
#3 ·
I have gauges and no silencer ring, haha Im jk I know these do nothing to help my performance.

I was gonna try sliding the stock plate FF and adjust star wheel for no smoke. I was given a #8 plate but I read not to run this on a 215 pump.

I wanna get a #10 eventually. Ill try stretching the spring, I want to eventually get a boost elbow and bump the boost to about 30 max.
 
#4 ·
GSK is the best for the 3-4 gap, I just run up 3rd longer and shift to 4th so its above like 1500. I tow my jeep around PA often and even on those long hills I never need to go below 4th.
 
#6 ·
I tow my 15000lbs gooseneck. In situations where I'm going up a steep hill and can't hit 4th I just wait a few seconds till I get to the top of the hill. It's not that big of a deal. But if I do shift to 4th on a hill I watch the egts to make sure it doesn't go above 1200. But yea, it bogs. That's just the way a 5 speed is. It's rarely an issue for me. I could put the 3000gsk in but like I said, not that big of a deal and I tow through some huge mountain country.
 
#7 ·
I was towing this:


Friends PS either has a bad VC gasket or CPS and ran like dog crap.

First, when I started to move my truck squatted bad in the rear, time for bags.

But I drove it like 3 miles down the road and couldnt get it into 5th between lights. Its one heavy trailer along with the truck
 
#8 ·
Also, it feels like my truck has no power past 1/4 throttle towing or not. It doesnt move or tow any faster by giving it more pedal, boost will build to max faster if I put it to the floor from a stop, but thats it. Even though its boosting faster the RPMs dont seem to raise any faster, and boost still doesnt push me into the seat until about 1800-2200 rpms.
 
#9 ·
Sounds like theres an issue there. My rig has a 180 pump with a #10 self cut plate, boost elbow, 4" turbo back. So I'm thinking 265ish hp and maybe 550tq. Cant be much more than that, probably less. It squats down but that's what happens when I put 2500# of pin weight in the bed.
 
#10 ·
Ive been reading about FP, Im gonna check two things.

I have an eliminated FSS and use a choke cable, The PO might not have made it so it throws fully.

Next im gonna try and stretch the spring on the OFV and maybe add a pen spring.
 
#18 ·
I have a brand new Fuel filter on my prime loc and I cleaned the prefilter.

Yep, solve your fuel pressure issues first. Change filters, OFV, check the shutoff solenoid etc. Something is off someplace. THen, read the FAQ's about turning these things up. You can get a fair amount of free horsepower and torque for relatively little effort. You already have gauges, and you're obviously watching the EGT already, so turn her up!
With the mods done to my truck (in my sig) I can tow my 10000 lb boat uphill in 5th gear at 70 mph all day long....
Im going to be turning her up soon. I was just slowing checking out issues to make sure something I did doesnt cause them. Call me crazy but I go slow with power mods, I make sure vehicle is 100% and check it after each mod.

I like to hang in fourth on the highway. 4.10's would make fifth gear towing almost required in my eyes. With my 3.54 gearing I don't have any issues.
It's almost more desirable for me to tow in fourth. At 60+, the engine is much quieter at 2500-2600 rpms than what it would be running in fifth.

Towing 15000
Why would you burn the extra fuel of 4th gear? Are you towing hill/mountains? In delaware its flat, maybe slight incline, Jersey too. I put it in 5th and hover 1800rpm whenever I can. I try to stay 55-65 on highway. But I dont let the engine lug 5th, if so I downshift. I guess towing your weights its prob ideal.

I just did the BIC pen spring OFV mod. Boosted from 15-16 psi to 37 constant. Feels a lot smoother now and possibly a little more peppy.

I still need to check whether my modded fuel shut off is opening the pump all the way. I believe it is, but well have to see.
 
#12 ·
Yep, solve your fuel pressure issues first. Change filters, OFV, check the shutoff solenoid etc. Something is off someplace. THen, read the FAQ's about turning these things up. You can get a fair amount of free horsepower and torque for relatively little effort. You already have gauges, and you're obviously watching the EGT already, so turn her up!
With the mods done to my truck (in my sig) I can tow my 10000 lb boat uphill in 5th gear at 70 mph all day long....
 
#13 ·
You aren't gonna be great towing with 3:55 gears either.
 
#15 ·
No? Why is that? They worked great for me pulling 22k up the pass between San Angelo and Midland, 6% grade for two miles.
 
#16 ·
I like to hang in fourth on the highway. 4.10's would make fifth gear towing almost required in my eyes. With my 3.54 gearing I don't have any issues.
It's almost more desirable for me to tow in fourth. At 60+, the engine is much quieter at 2500-2600 rpms than what it would be running in fifth.

Towing 15000
 
#17 ·
Fair enough, I dont tow in fifth though when I am that heavy.
 
#19 ·
Sometimes I go to fifth but only on flats. I'd rather burn the extra fuel than grenade it by pushing it up some of the hills I've towed up in fifth. Also like I said , fourth is more desirable @ 60 because the engine is so much quieter and I don't like towing much over 60. Not this trailer.
 
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