Tuning Assistance

[dlg]

Let me start by saying I know there is a lot of existing information on the forums but I have never tuned any gas or diesel vehicle before, and this is my first diesel vehicle so i'm just not comfortable figuring it out on my own. If you are annoyed by folks who ask already answered questions I would just ask that you move on to a different post.

 

I have one generic question and then a few tuning related questions.

 

First, the general question. What is the best way to go about finding a shop, or a person near me who has the ability to enable the factory high idle and 3 cylinder high idle in my ECM. I am located in Omaha so bonus points if you already know somebody or some place. I do have access to an Autel scan tool that I usually use for reading codes, is it possible I can do it myself? The Autel does a lot of things that I have never messed with so I don't know its capabilities.

 

On to the tuning questions. I would rather pay someone experienced to help me with this, rather than try to figure it out myself and mess something up. If you are interested in helping me, please let me know.

 

I have an (as far as i'm aware) stock 1999 Ram 2500 and I have installed a Quadzilla. I have highway gears and so towing at speeds over 60 can be tough. I don't want to change the gears out because I don't tow that often but I drive on the interstate a lot so as far as pros/cons go the highway gears are better for me. I also don't tow anything that heavy, mostly an enclosed trailer with a lot of drag and not much weight. From what I can tell after installing the tuner the real additional power doesn't kick in until after 2000 rpm which from what I can tell is based on the timing settings in the tune. Unfortunately my overdrive kicks in around 45-50 mph and I don't hit 2000 rpm until about 70 so it's still tough to get from 45 to 70 even in PL10. Once I'm at or over 70 everything is great. So is there anything I can change to safely get some of that additional power between 1500 and 2000 rpm?

 

Second question. The Quadzilla has a 'mileage' setting. I have not had it installed long enough to know how effective that is, but is there anything I can change on this power level to make it more effective without causing issues? This would only be used when i'm running empty on the highway. If I was towing or hauling I would use the stock setting or one of the increased power levels.

 

Third question. Should I add the optional fuel pressure sensor? I do not intend to do any additional mods to the engine.

 

I don't really want anything crazy here, I don't want to race this thing, I don't want to do a bunch of crazy mods, and honestly from what I can tell I don't even really need PL10. Just going to 5 or 6 makes the truck much more drivable when towing. All I want to do is make the truck as driveable as possible without doing anything that could damage the engine. 

 

Thank you for your time.

[Tractorman]

@Mopar1973Manwill likely reply at some point, but I know he will want a bit more information.  He is the residential expert regarding the Quadzilla.  He can provide you a custom tune.

 

Automatic transmission (sound like an automatic from you post)?

 

What is your tire size?

 

What is your axle ratio?

 

Still have stock injectors and turbo?

 

- John

Edited December 17, 2023 by Tractorman

[Mopar1973Man]

@Tractorman is right on the money.

 

Tire size

Gear ratio

Transmission type

Turbo 

Injectors (size and pop pressure)

 

Towing you want RPMs between 2,000 to 2,500 for optimal power. So if you are running oversized tires on 3.55 will make your EGTs high.

 

Example of Beast at 82 MPH.

 

So optimally you want a final ratio of 3.73 for towing and highway. Like myself I'm running 245/75 R16 tires on 3.55 gears which nets me a 3.69 final ratio. Screenshot is about is my Beta test of going for high MPGs during winter and experimenting with higher coolant temps to gain a little more power and lossless some of the waste into the coolant jacket.

 

 

Another view of running I84 at 80 to 82 MPH. Oh just keep in mind I'm running 2,450 to 2,500 RPMs at 80 MPH so as you can see good eco numbers.

Edited December 17, 2023 by Mopar1973Man

[dlg]

I'm aware what RPM I need to run at, running at speed is not the issue now that the tuner is installed. Both of your photos are at speed. As I said in the first post my issue is getting to speed. It is an auto trans and it switches to OD at 45 mph or 50 mph and 1500 rpm so from 45 mph to 75 (Where i'm at 2200rpm) I still have no power because the tuner doesn't kick in until 2000 rpm. From 2000 rpm on the tuner makes a huge difference. From 1500 rpm to 2000 rpm the truck still struggles and the tuner seems to make no difference I need more power from 1500 rpm to 2000. The problem is if it's windy I can't even get to 2000 rpm (70mph). 

 

I'm fairly sure I said this in the first post but stock everything. Stock auto trans, stock tires (245/75R16), stock injectors, stock turbo. 3.54 rear end gears, I have no idea what the final drive is or how to figure it out. 

[Mopar1973Man]

That's all timing based then. The only clue I can give is make sure your retarding properly during acceleration. That will allow for building boost.

 

Transmission wise with the torque converter lock / unlock at 45 is AC noise issue from bad grounds. I highly suggest you do the W-T ground wire mod. 

 

 

[Tractorman]

14 hours ago, dlg said:

I'm fairly sure I said this in the first post but stock everything. Stock auto trans, stock tires (245/75R16), stock injectors, stock turbo. 3.54 rear end gears, I have no idea what the final drive is or how to figure it out.

 

You did say in your first post that you thought everything was stock, but you didn't mention whether the transmission was an auto or manual.  This is important because the overdrive gear ratio in an auto transmission is .69:1, a much taller gear than that of an overdrive gear in a manual transmission.  I deduced that it was an automatic because you mentioned that, "overdrive kicks in around 45-50 mph".  Also, knowing the specific tire size and the specific axle ratio is very helpful.   The tire size on your truck is the best match for the axle ratio and automatic transmission in your truck to get the best performance from the engine in your truck.

 

I will try to answer some of the questions you asked, but didn't get answered.

 

On 12/17/2023 at 8:26 AM, dlg said:

First, the general question. What is the best way to go about finding a shop, or a person near me who has the ability to enable the factory high idle and 3 cylinder high idle in my ECM

 

Finding a reputable shop can be difficult.  Finding a reputable shop that knows and understands VP44 engines can even be more difficult, but that is what I would search for.  A dealer or a shop with specialized tools may be able to help you with the enabling of the high idle and 3 cylinder idle.  I have this feature enabled because I have a Smarty S03 tuner.  It may be possible (not sure about this) that if you can find someone with the Smarty S03 who is willing to connect to your diagnostic port and lock in the VIN# one time, the feature may be enabled.  Again, not sure about this.

 

On 12/17/2023 at 8:26 AM, dlg said:

Second question. The Quadzilla has a 'mileage' setting. I have not had it installed long enough to know how effective that is, but is there anything I can change on this power level to make it more effective without causing issues?

 

@Mopar1973Man, can you answer this question?

 

On 12/17/2023 at 8:26 AM, dlg said:

Third question. Should I add the optional fuel pressure sensor?

 

Do you already have a fuel pressure gauge on your truck?  If not, this would be a good option.  It is important to ensure that there is always a positive pressure (lift pump pressure) at the inlet of the VP44 fuel injection pump (a specific value is not important).

 

14 hours ago, dlg said:

From 1500 rpm to 2000 rpm the truck still struggles and the tuner seems to make no difference I need more power from 1500 rpm to 2000.

 

First, let me make it clear that I have no experience with the Quadzilla tuner, but I do have experience with tuning a VP44 engine.  From what I understand about the Quadzilla, is that you have a lot of control when setting fueling and timing parameters for varying engine rpms and throttle positions.  It seems to me that you are having limited fueling in the 1500 - 2000 rpm range.  If you are in overdrive and the torque converter is locked, are you getting any black smoke from the tailpipe when accelerating hard at 1500 rpm?  If the tailpipe is clear, I would start adding fuel in this rpm range. 

 

I also understand that the Quadzilla is one of the tuners that is more difficult to understand how to set the desirable parameters with fueling and timing.

 

I am using a Smarty S03 tuner with a manual 6 spd transmission.  I have it set to start fueling hard from about 1300 rpm, so by 1500 rpm the engine is delivering a lot of torque (without smoke).  I am doing this with stock timing. 

 

On 12/17/2023 at 8:26 AM, dlg said:

All I want to do is make the truck as driveable as possible without doing anything that could damage the engine. 

 

I would be more concerned about the stock transmission than the engine.  The lockup converter clutch is a weak link, especially at lower engine rpms under high engine torque.

 

@dlgasked, "On to the tuning questions. I would rather pay someone experienced to help me with this, rather than try to figure it out myself and mess something up."

 

@Mopar1973Man, can you build him a tune?

 

- John

Edited December 19, 2023 by Tractorman

[Mopar1973Man]

49 minutes ago, Tractorman said:

The Quadzilla has a 'mileage' setting.

No such thing really. Mileage is all based on how the tune is built and how the truck is driven from there. I can be on any level I wish which with drive the same in every manner but the only thing levels do is just cut the maximum fuel to different limits. 

 

Level 2 - Stock Fuel only

Level 3 - CANBus fuel only which is about 60 HP jump.

Level 4 and up - CanBus + Plus Wire Tap (Level limits the wire tap)

 

In my case, the only time I use level 2 is during the winter to prevent spike of power causing wheel spin. Even with level 3 and up I can still do very well just you have to think more power quicker to destroy the MPG number.

 

55 minutes ago, Tractorman said:

@dlgasked, "On to the tuning questions. I would rather pay someone experienced to help me with this, rather than try to figure it out myself and mess something up."

 

@Mopar1973Man, can you build him a tune?

 

All you have to do is go over to the forum for submission for a tune and answer some basic questions. Then I build a tune based on the information given. This base tune will need work and effort. But once the first tune is built and uploaded then you will make your payment for said tune and the forum will keep our notes in order. I will create as many new versions updated based on what is not quite right. All previous versions will saved in your download section so for example 1.0.0 base tune, then we make 1.0.1 and good. Now you request something different I made 1.0.2 and it is a flop that runs poorly with performance problems. We can back up to 1.0.1 and then spur off a new version of 1.0.3 which then we never have to rebuild from the ground up. 

 

https://mopar1973man.com/forum/216-custom-quadzilla-tune-request/

 

[dlg]

5 hours ago, Mopar1973Man said:

All you have to do is go over to the forum for submission for a tune and answer some basic questions. Then I build a tune based on the information given.

 

I will do that, thanks

 

 

5 hours ago, Mopar1973Man said:

No such thing really. Mileage is all based on how the tune is built and how the truck is driven from there. I can be on any level I wish which with drive the same in every manner but the only thing levels do is just cut the maximum fuel to different limits. 

 

I based that on their website. PL02 is listed as a mileage setting. I guess I misunderstood what this means

 

 

 

6 hours ago, Tractorman said:

Finding a reputable shop can be difficult.  Finding a reputable shop that knows and understands VP44 engines can even be more difficult, but that is what I would search for.  A dealer or a shop with specialized tools may be able to help you with the enabling of the high idle and 3 cylinder idle.  I have this feature enabled because I have a Smarty S03 tuner.  It may be possible (not sure about this) that if you can find someone with the Smarty S03 who is willing to connect to your diagnostic port and lock in the VIN# one time, the feature may be enabled.  Again, not sure about this.

 

I also believe this to be accurate based on what I have read. I have tried posting on local forums for anyone with a Smarty wanting to make a quick couple of bucks but have not had any success. You don't think I can enable it with an Autel scan tool?

 

 

6 hours ago, Tractorman said:

Do you already have a fuel pressure gauge on your truck?  If not, this would be a good option.  It is important to ensure that there is always a positive pressure (lift pump pressure) at the inlet of the VP44 fuel injection pump (a specific value is not important).

 

I do not, I will probably add this. Quadzilla shows adding one via 2 different size tee fittings or a banjo bolt but doesn't offer any explanation as to when to use which option. What is the best way to add this.

 

[Mopar1973Man]

Level 2 caps any fuel table to 100% stock fuel. Then allows the custom timing. Now this points out that the custom tune fuel table it restricted. Now the timing table is going to be the most important thing about the tune. Being able to get a flat engine load at 65 MPH then we set cruise range. So as long as your engine load is low and boost is low you can have 24° to 26° BTDC at 2,000 RPM and do it safely. 

 

Another trick is if you have the transmission temp sender plugged into the oil test port on the oil filter housing you can verify you amount of timing by your oil temperature. Proper timing your engine oil temparure should hover about 165 vs 195 coolant. Now if engine oil temperature is great or equal to coolant temperature your timing is too advanced.

 

Any changes that add more to temperatures or increase engine load your going the wrong way. When the tune is done right EGTs should be so low that in the winter I can drive 15 miles and barely get the truck to full temperature. 

 

 

[Tractorman]

2 hours ago, dlg said:

You don't think I can enable it with an Autel scan tool?

 

I have never used an Autel scan tool, so I don't know the answer, but I highly doubt that any of the scan tools will have the ability to enable the high idle / 3 cyl idle feature. 

 

2 hours ago, dlg said:

Quadzilla shows adding one via 2 different size tee fittings or a banjo bolt but doesn't offer any explanation as to when to use which option. What is the best way to add this.

 

The banjo fitting in the photo below should be the fitting you are looking for.  All that has been added in the 1/8" NPT threaded port in the end of the bolt.  You will find the banjo bolt that you need to replace is fitted at the inlet of the VP44 injection pump.

 

- John

 

 

[dlg]

16 hours ago, Mopar1973Man said:

Another trick is if you have the transmission temp sender plugged into the oil test port on the oil filter housing you can verify you amount of timing by your oil temperature. Proper timing your engine oil temparure should hover about 165 vs 195 coolant. Now if engine oil temperature is great or equal to coolant temperature your timing is too advanced.

I do have the oil temp probe hooked up

[dlg]

On 12/19/2023 at 7:49 AM, Mopar1973Man said:

Transmission wise with the torque converter lock / unlock at 45 is AC noise issue from bad grounds. I highly suggest you do the W-T ground wire mod. 

 

I did this mod this weekend and it didn't seem to change anything. Transmission still goes in to lockup almost immediately after going in to 4th, pressing the O/D off button kicks me all the way down to 3rd instead of just taking off the lockup, and sometimes while driving at constant lower speeds the transmission shifts randomly and then back. 

[Tractorman]

1 hour ago, dlg said:

Transmission still goes in to lockup almost immediately after going in to 4th,

 

This is normal operation.

 

1 hour ago, dlg said:

pressing the O/D off button kicks me all the way down to 3rd instead of just taking off the lockup,

 

This is also normal operation.  If the transmission is in fourth gear, pressing the Overdrive button "off" is commanding the transmission to downshift to third.  There is no "switch" to unlock the converter.

 

At what speed and which gears?  Or is the converter locking and unlocking instead?

 

- John

Edited January 1 by Tractorman

[Mopar1973Man]

Did you test for AC noise? Did you bench test the alternator? Have you done the W-T ground wire mod? All this fixes the lock and unlock. 

 

Now as for dropping into 4th quickly. You might gain some if you readjust your Throttle Valve cable which you might be able to delay it slightly.

 

I had the same problem with my 1996 Dodge 1500 5.9L V8 5.9L. That 46RE (including 47RE and 48RE) was known to fall into 4th early. 1st through 3rd is all hydraulic controlled in the valve body but 4th is electronic controlled by the PCM. Hence the name 47RE which is 4 gears, TQ rating of a 7, and it rear wheel drive, Electronic shift. RH would of been Rear Wheel drive and Hydraulic Shift.

[dlg]

11 hours ago, Tractorman said:

 

This is also normal operation.  If the transmission is in fourth gear, pressing the Overdrive button "off" is commanding the transmission to downshift to third.  There is no "switch" to unlock the converter.

 

At what speed and which gears?  Or is the converter locking and unlocking instead?

 

 

That seems like a bad design. There are many times when being in 4th with no lockup would be hugely beneficial.

 

I don't know which gears. It happens randomly and when I notice it I have no way to know which gear I was in. If I had to guess at the speed I would say between 25 and 35 but again I haven't really been documenting it. I'll have to pay more attention. The only thing I can say for sure is it definitely shouldn't be doing it. I will be driving at a constant speed on level ground and it will downshift for a second or two, then upshift. No change in throttle, no change in load. 

 

 

2 hours ago, Mopar1973Man said:

Did you test for AC noise? Did you bench test the alternator? Have you done the W-T ground wire mod? All this fixes the lock and unlock. 

 

I don't know what you mean by bench test the alternator but no I did not. It's brand new and this was an issue with the old alternator. Yes I did the mod, no I did not test for noise. The guide you linked does not describe where to test for ac noise, it just says to do it.

Edited January 1 by dlg

[Tractorman]

30 minutes ago, dlg said:

That seems like a bad design. There are many times when being in 4th with no lockup would be hugely beneficial.

 

When would it be hugely beneficial to be not locked up in 4th?  An unlocked converter generates heat, lots of heat - the heavier the load and the further the throttle is pressed, the more heat will be generated.  When the converter is locked, all of the engine power is transmitted to the rear wheels (just like a in a manual transmission), thus generating far less heat and putting much more power to the wheels.

 

To me the "bad design" is there really should have never been only four gears place behind a high torque at low rpm diesel engine in the first place.  And even worse, only the two top gears allow converter lock up.  Simply not enough gears (or converter lock up) to keep the engine in the peak torque range.  This is why I drive a 6 spd manual transmission - always the right gear available and no slippage, no matter how demanding the load is.

 

57 minutes ago, dlg said:

The only thing I can say for sure is it definitely shouldn't be doing it. I will be driving at a constant speed on level ground and it will downshift for a second or two, then upshift. No change in throttle, no change in load

 

Gears one through three are shifted hydraulically.  Fourth gear is shifted electrically with a solenoid.  Converter lock up will happen only in third or fourth gear.  If there is a full gear shift happening, there will be a significant engine rpm change.  If the converter is locking and unlocking, there will about 100-200 rpm change under light throttle.  See if you can determine which is happening.

 

Sounds to me like a converter unlocking and locking under a steady throttle - and you are right, that should not be happening.  The PCM supplies the signal for converter lock up.  When unwanted converter unlocking and locking occurs, it is usually an electrical field interference generated from another electrical source.  The PCM stores this unwanted information until it determines that is normal and then changes the signal to adapt to the new normal.  

 

One thing to try.   Disconnect the ground at both batteries.  Turn the ignition switch to "run" position.  Slowly depress the throttle to the floor and slowly let it return.  Do this two or three times.  Hookup the batteries and drive the truck.  Did the problem disappear?  If so, this confirms that you are having an electrical interference with the torque converter lock up signal.  The symptoms will return.

 

- John

[Mopar1973Man]

Technically the ECM and PCM do not store any drive information. The only thing it can store is the error codes and disconnecting the battery does not erase codes or any software being the software is flashed to the EPROM. The codes are stored in NVRAM like a thumb drive.

 

Like I said most of the hunting is caused by the AC noise levels. Still, say to test the alternator and the charging system. Even weak batteries with a bad alternator can produce some serious AC noise exceeding 0.1 volts which is damaging to the ECM, PCM, and the VP44.

[dlg]

1 hour ago, Tractorman said:

 

When would it be hugely beneficial to be not locked up in 4th? 

When going up a steep hill at interstate speed where I don't have enough power to maintain interstate speed. I will give you an example that happens constantly. Cruising along at 75mph in 4th gear locked, cruise control engaged. Truck does not have enough power to maintain speed at this gear ratio. 75mph for me is right at 2000rpm so slightly under the peak power band. The truck slows down continuously until around 40mph where I am well under the power band of the engine and am losing speed rapidly, then the transmission skips 4th unlocked to go all the way to 3rd. Now i'm at 2500, at the very top of the power band. Then you gain speed until about 55mph and it skips 4th unlocked to go to 4th locked and I again lose speed. 4th locked makes the engine run at too low of an RPM and 3rd is too high. Yes I could hit the OD off button and maintain 55mph but I would be doing that at over 3000rpm and at a terrible fuel economy. If the transmission were to stay in 4th unlocked I am 100% confident I would be able to maintain at least 55mph if not 60 or 65 up the same hill at a reasonable rpm.

 

Yes I understand a torque converter makes heat, but when it skips all the way down to 3rd isn't it making the same amount of heat? Am I not making heat in 1st or 2nd? I just took my 16 ft trailer loaded up a 45 degree hill to a friends house this weekend. It's a very long and very steep residential hill and I did the entire thing in 1st gear, presumably slipping and making heat the entire time. So why is that okay but doing it in 4th for a hill is not okay?

 

It seems to me that the lockup should be more like a pseudo 5th gear and all "5" gears should be usable at some point. If 4th unlocked is "never to be used", why does it even exist? If the only time the transmission should ever be in 4th is if it's locked, why not skip 4th unlocked. When I accelerate from 0 to 70 why does it go 1, 2, 3, 4 unlocked, 4 locked. Just go straight from 3 to 4 locked if that's the only acceptable transmission state. That would be like on my 5 speed manual transmission car if the owners manual said "when accelerating you can use 4th for a few seconds but never drive in 4th, only drive in 3rd or 5th."

 

The whole thing doesn't make any logical sense to me.

51 minutes ago, Mopar1973Man said:

Like I said most of the hunting is caused by the AC noise levels. Still, say to test the alternator and the charging system. Even weak batteries with a bad alternator can produce some serious AC noise exceeding 0.1 volts which is damaging to the ECM, PCM, and the VP44.

The batteries are also brand new in the last year. When I got the truck it did it, when I replaced the batteries because they were weak it still did it, then when I replaced the alternator because it was also weak it still did it. Now I have no cranking problems even in very low temps and I charge at 14.5 volts at 1500rpm so the batteries and alternator are not weak.

As I said in the last post I the ground wire mod article does not say where to measure AC voltage, it just says to measure it. I would be happy to do it, I just need to know where. Battery to battery, battery + to engine block, battery - to engine block, alternator charge output to battery + or battery -, alternator to engine block? There are a lot of ways to measure for errant voltages. 

[Mopar1973Man]

Did you have the new alternator tested? I've seen new in the box that has failed the bench test more than once.

 

Another way to test unplug the field lead on the alternator. It should stop the lock unlock issue. This will show that alternator is bad.

 

As for the power issue. What size tires are you running and what axle ratio does your truck have? Like myself I'm running 245/75 R16 tires on 3.55 gears which makes my final ratio 3.69. This makes my 66 MPH at 2,000 RPMs at 80 MPH 2,450 RPM. I can tow my 31 foot RV over a 7% grade on cruise control and never go high on EGTs nor lose speed.

[Tractorman]

@dlg , you bring up a lot of good points and I completely understand your frustration.  A stock 47RE is not a good transmission to have behind a Cummins 5.9 liter engine.  You have listed all of the shortcomings of this application very well. 

 

1 hour ago, dlg said:

If the transmission were to stay in 4th unlocked I am 100% confident I would be able to maintain at least 55mph if not 60 or 65 up the same hill at a reasonable rpm.

 

Well, you may or may not, but I am going say probably not.  The Cummins engine develops peak torque at about 1600 rpm.  It maintains close to peak torque even above 2,000 rpm.  If the truck loses road speed in 4th gear locked up climbing a grade, this means that the load has exceeded the full torque capability of the engine.   If the converter did unlock you would have the slight benefit of a simulated partial downshift that would provide slightly more torque to the rear wheels, but that added torque would be cancelled immediately by the power loss from heat generation of a slipping torque converter.   This means less power to the rear wheels.  And, this excessive heat will be damaging to the transmission.   

 

So, when your transmission downshifts to 3rd, you have much more torque multiplication to the rear wheels and when the converter locks you will now even have more torque to the rear wheels.  The truck will accelerate easily.  Another downside to the overdrive gear (4th) on the 47RE is that the gear is too tall.  The overdrive gear in the manual 5 and 6 spd transmission is not nearly as tall, thus better aligned with the Cummins engine torque for better performance. 

 

1 hour ago, dlg said:

Yes I understand a torque converter makes heat, but when it skips all the way down to 3rd isn't it making the same amount of heat?

 

No, because the converter will immediately lock up and all of the engine torque will go to the rear wheels

 

1 hour ago, dlg said:

Am I not making heat in 1st or 2nd?

 

Yes. but not as much heat for the same grade. You will have much more available torque because of torque multiplication from the gears as you shift to lower gears.  So, not a much engine power is needed.

 

1 hour ago, dlg said:

I just took my 16 ft trailer loaded up a 45 degree hill to a friends house this weekend. It's a very long and very steep residential hill and I did the entire thing in 1st gear, presumably slipping and making heat the entire time. So why is that okay but doing it in 4th for a hill is not okay?

 

Hopefully that wasn't really a 45 degree hill.  That would be 100% grade.  A 10% or 15% grade is very steep.  Regardless, yes, you would be making lots of heat.  It really is not okay, but that is the product you have (the 47RE) and you can't really do anything about that particular situation.

 

1 hour ago, dlg said:

When I accelerate from 0 to 70 why does it go 1, 2, 3, 4 unlocked, 4 locked. Just go straight from 3 to 4 locked if that's the only acceptable transmission state.

 

The transmission cannot be locked during a shift.  If it was locked, the shift would be jarring and damage to the transmission would likely occur.  It would be like speed shifting a manual transmission.

 

Most people who have used this transmission for towing have significantly upgraded the transmission - mainly a lower stall speed heavy duty triple disc torque converter (converter lock up clutch), higher line pressure, heavier clutch packs, and converter lockup available in every forward gear.  These amenities allow for the use of an engine tuner that will provide the needed engine torque to easily climb grades in fourth gear locked up.  Both the engine and transmission will be happy.

 

- John