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Towing Help (Concerns)


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Not really virgin but am to this truck and trailer. (I've towed a 20 something foot wells cargo with a 460cc Ford when I did roofing). 

Anyway, here are my questions. I just picked up a 33' fifth wheel travel trailer. Dual axles, 8400lbs dry. 

My truck. 98.5 24v with a bhaf and 4" straight pipe. 285/16 tires. 

1. On the way home the truck had a hard time on hills. For example. Went from 65mph down to 45mph on a moderate grade hill. About a half mile long hill. Rpms were about 2800 the whole way up the hill and I was slightly worried about what egt's might have been. I do not have any gages. 

2. I had adjusted trailer brakes from my controller to just shy of lockup. I hit my brakes on the freeway (light to moderate pressure) and the truck pulled hard to the right halfway onto the shoulder. Kinda scary. Then right by my house I have a medium slope hill coming down to the house and it's only a 1/4 mile long, yet when I got to the bottom, there was a very strong brake smell. I inspected the truck and trailer, and my driver front wheel was very dark with dust and smelled horrible. Other side was fine. 

So, I need some input. 
1. I would love to upgrade my brakes, but after researching a bit, I guess I can't put the 3rd gen calipers on my truck. Sad. What's the next best thing? I wanna get new calipers pads and rotors. 

2. Should my truck struggle this hard towing at my power level and weight? If yes. Then what can I do and how much? I was thinking about getting a smarty and some 75lbs injectors. What other supporting mods do I need. Brands and prices? Probably an egt and tranny temp gage? (I don't really hot rod the truck so will my 47re take it?)  
All input is welcomed. Thank you. 

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One thing you need to know is how much the trailer actually weighs. Manufacturers dry weight means nothing. You need to know what weighs. Get on Cat scale or something similar and weigh it. I pull a 15k pound fifth wheel with the stock brakes and they work fine in conjunction with the trailer brakes. I have a exhaust brake which helps also. It does sound like you need to rebuild your calipers if they are pulling that bad. 

As far as pulling the hill, if your rpm stayed a steady 2800 your tranny is slipping and it will not take much of that for it to burn up. The stock auto in these truck is a weak link especially carrying a heavy load. Unless you have 4:10 gears in the rear the bigger tires are just multiplying the problem. If you have a tuner or anything adding power well thats another multiplier. I will let the folks that know the autos give you better advice than I can.

 You can go to your profile page and fill out you signature with any mods you know are on the truck. that would help alot. All can see what you are working with then. I you have no gauges a FP, EGT, Boost, and tranny temp gauges are all good to have. Tranny temp for sure with an auto. There are some basics. Lets what others will add.

 

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First off dry weight is meaningless. Like my RV dry weight is 6,800 pounds. Actual scale weight is a worlds different. As you see it much heavier than dry weight so just forget that number and go find a scale. 

2cqfx9w.jpg

 

2 hours ago, Florin1 said:

1. On the way home the truck had a hard time on hills. For example. Went from 65mph down to 45mph on a moderate grade hill. About a half mile long hill. Rpms were about 2800 the whole way up the hill and I was slightly worried about what egt's might have been. I do not have any gages

 

2 hours ago, Florin1 said:

My truck. 98.5 24v with a bhaf and 4" straight pipe. 285/16 tires.

 

Tires are killing your power ditch the 285's to gain back your gearing. So you 3.55 gear ratio is now 3.42 which is making the truck work harder. I'm going to bet your EGT's were through the roof even for a stock truck. I highly suggest you get boost, pyrometer, fuel pressure and transmission temperature gauge. Very important to monitor these while towing. 

 

gear ratio.jpg

 

2 hours ago, Florin1 said:

I guess I can't put the 3rd gen calipers on my truck. Sad. What's the next best thing? I wanna get new calipers pads and rotors. 

 

If you ditch the 285's tires you won't need the 3rd gen calipers. I'm running 235's and exhaust brake my brakes are going to clear 200k miles. My first set of brakes lasted till 185k miles. I travel the mountains of Idaho with grades up to 16%. Again tire size makes a huge difference. 

 

oa7sr4.jpg

 

2 hours ago, Florin1 said:

Should my truck struggle this hard towing at my power level and weight? If yes. Then what can I do and how much?

Again... Tires. The tires your running has altered the final gear ratio so it like driving a gear higher all the time. I ran for years just stock injectors and Edge Comp. Over the years I've been upgrading now hopping up to +75 HP injectors with the Quadzilla. Even with my +50HP and the Quadzilla I was able to get the rear tire to light up towing trailers. Even this trailer full of 10,000 pounds of hay...

 

286vj2r.jpg

 

Here is stock 265's compared to 235's. Basically 1.1" narrower 1mm taller but I'm 23-25 pounds lighter on the axle. Rotational mass reduction!

tires1.jpg

 

Now your setup... 265's vs 285's. Gear ratio has been altered. So now the leverage force to stop the truck have been weakened because for the wheels size giving more leverage against the brakes. Then since the tires are large they are heavier (more rotational mass) and more strain on the transmission. Basically the heavier the flywheels (wheels & tires) the more difficult it is to stop them. 

tires2.jpg

Edited by Mopar1973Man
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26 minutes ago, Florin1 said:

Thanks for the input so far. Will update sig 

 

no idea how to update sig. 

Go to the top right of the page and click on your screen name. From the drop down menu pick account settings. You will see signature on the left had column. Click it and add what you know. You can look at mine and Mike's at the bottom of the posts to get an idea of what to put there. If you are not sure whats on the truck we can help figure that out.

Edited by dripley
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1 hour ago, Me78569 said:

Also no 3rd gen brakes on an early front axle

So what's my option. Just buy reman calipers and new slotted rotors? Also I saw somewhere mentioned that I. An use chevy 1 ton cylinders in the rear? Any info on that? Those things are cheap! 

Michael. I really appreciate your input and time you took to explain. And when it's time for new tires, I'll downsize. But these tires are in really good condition so I'm not gonna toss em. But say if I go to a 17" wheel, what is the correct tire size for my truck? 

As for the gages, what do you guys run? Where did you buy? Part numbers?

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I don't have a link handy but try Vulcan performance for isspro ev 2 gauges, you will need pyro, trans temp, fuel pressure for sure and then boost if you can swing all 4. As far as brakes I would not go with extra performance parts, stock oem is just fine, as far as my opinion slotted rotors are a waist of money, and the Chevy 1 ton brake cylinders too. If your truck has the rear load leveler rod on rear drums just in hook it and makes a world of difference on the rear drums.  Along with keeping your truck brakes up it's highly important to keep your trailer brakes up too, as that's going to be a lot of your stopping power.

 

I run a 47 re slightly built with Billiet converter and stock valve body, I run 285/75/16 with stock engine and pull 19K with truck/30 ft. 5ver, and boat, and on 6-7 % grades up to 9 miles long I don't  see more than 2500 rpm and that's with keeping all my gauge readings within  tollerances. As far as your 2800 rpm on a hill that short, I would pull the trans dip stick and see if any signs of burnt fluid.

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I agree as far as slotted rotors, they're a waste of time/money, at least on our trucks. Just stick with the oem style. Are you positive your caliper is shot? I would for sure replace rotors and pads but what indications are you getting that your caliper is bad as well?

 

I'll throw in another vote for Vulcan and one phone call to Eric and he'll have you setup with every thing you need gauge wise in a nice package deal.

 

How many miles are on the truck/trans? Could just be long over due for a tune up or refresh. I'd also advise against adding any more power at this point, especially if you're seeing the issues you currently are. Adding power will only make things worse! I just recently added a quad xzt I forgot I had laying around and even though I drive like a granny and the trans is fine now, I'm fully anticipating needing to get my trans build soon, and that's not even counting towing. If I do tow, I turn that off.  

 

The tire size as Mike put, is really a huge factor. Currently on my 02 I have 315s on there and my 99 I have stock tire size. It's night and day how differently they drive. Granted, they're completely different trucks but the 99 with smaller tires is night and day easier to drive.

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Like Mike said, 285's while looking super hot on a stock height dodge, don't go well with towing, I've towed with 245's 265's and 285's and the 285's were kinda miserable.  By the sounds of it you have an automatic so you may even consider a 245 as that's what came stock on the older truck.  This all assumes you have a 3.54 gear ratio, if you've got 4.10's, then 285's aren't a bad match.  If you look under the hoot by the hood latch, it should say what gear ratio that axles are.

 

Now for the elephant in the room... 65mph down to 45mph while staying at 2800RPM screams that your Torque Converter was unlocked.  When towing that's a big no no, the TC is only about 65% efficient so only 65% of your power was going to the ground, and the other 35% was going into heat, which can fry a automatic transmission pretty quick if you're not careful.

 

A gentleman a while back who was in similar shoes asked how to get the most out of his rig, and got some pretty decent answers, you may consider checking his thread out here.  

 

 

As far as EGT's.  I wouldn't worry about them to much on a stock truck, we know Cummins tuned the engine so that it's basically indestructible in stock form.  And their '1250°F Maximum' was a catch all rating, as long as there are no crazy flatbill mods, and RPM's are above ~2200RPM, that '1250°F' rating goes out the window.  As long as it's not smoking, I could care less what EGT's are.  I had my truck up past 1600°F on multiple occasions in the 2500-3400RPM range, when I pulled the head everything looked spotless.

 

On your brakes, try applying only the trailer brakes using the controller, if the truck tries to pull to the side, then it's the trailer brakes that are causing the pull, so it's likely one side isn't applying.  If it doesn't then it's likely the truck.  For us 4x4 guys, on the front brake lines there's a steel bracket that holds the brake line to the frame, these brackets can rust and pinch the brake line off causing a lack of braking, and the brakes to drag.

 

Typically though, if the brakes are making the truck pull to one side or the other, it's the rear brakes.  So get yourself some Chevy wheel cylinders, and while installing, double check everything looks good, then adjust both rear brakes correctly.  Sometimes  you can adjust the brakes by simple going reverse at about 15-20mph and then apply the parking brake.  Do this forwards and backwards a couple times and your problem may be fixed.  Regardless, the Chevy wheel cylinders are a decent upgrade that help considerably.

 

If you're wanting to up the performance, a shift kit goes a long ways in helping your auto hold the power, it raises the hydraulic line pressure which holds the clutches tighter preventing them from slipping.  Here's a good auto tranny upgrade list.

http://www.cumminsforum.com/forum/94-98-drivetrain-except-engine/452157-proper-upgrade-list-transmission.html

 

If you play around with the 'OD Off' button, and practice trying to keep the TC locked, then you should be able to get a bit more out of your truck.  For reference, with my 97 auto, full engine power was achieved by 60% throttle, so any more than that was pointless, however, if I went past 90% throttle, it would unlock the TC.  So when towing up hills, I would make sure to keep it between 60% and 90% throttle to get full power without unlocking the TC.

 

Best of luck!

 

 

 

 

 

 

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1. So on the suggested gauges, do they come with everything needed to install? Like the egt sensor? Nipple for tapping into a boost line, FP sensor?

 
2. I don't know if my truck has a rear loader leveling rod... it's a 8800lb gvw. 
 
3.  I just serviced my tranny a month ago. Replaced the fluid and adjusted the two bands. Truck is at ~240k. 
 
4. Notlimah- I'm fairly positive it's my driver side caliper. The truck pulled before I ever towed, and was way more noticeable yesterday when I towed. And when I got home there was visibly more brake dust on LF wheel than the rest. It also smelled very hot. And this morning on my way to work it's more noticeable post trailer towing. I might be dragging that caliper. Now that I think about it, the previous owner said he replaced a caliper, I just can't remember which one. So I'm wondering if it's a recurring problem. 
 
5. So if I'm gonna buy new calipers rotors and pads, what you guys recommend? Just reman calipers and what pads? Thanks. 
 
6. Yes I have the 3.54 gear ratio. And I turned off OD as I approached the hill anticipating it. I probably had my foot down to 80-90% throttle by the time I got to the top. 
 
7. Haha, no crazy flat bill mods. Just exhaust and air filter. Although I'm thinking of doing that TC lockup switch mod next. I got a big camping trip planned for Memorial Day. It's a 200 mile drive up through a mountain pass. 4000' elevation. So I wanna get the truck ready for that. 
 
8. I'll check brake lines to make sure there's no pinching. Do you have a link to the chevy cylinders upgrade? Or is it literally just swapping out cylinders?
 
Thank you all for all the input so far guys. This is all good info. Keep it coming. 
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16 minutes ago, Florin1 said:

 

1. So on the suggested gauges, do they come with everything needed to install? Like the egt sensor? Nipple for tapping into a boost line, FP sensor?

 

 

No typically they do not. Fuel pressure might take a bit of creating. Boost do not get the boost bolt. Just use the pipe plug in the side of the block. Way too many time that boost line gets broke off or the boost bolt snap in the manifold being hollow and attampting to tighten enough to prevent boost leaks. Trans temp again your going to have to get creative and EGT does come with the probe and everything but you have to drill and tap the manifold.

 

16 minutes ago, Florin1 said:

5. So if I'm gonna buy new calipers rotors and pads, what you guys recommend? Just reman calipers and what pads? Thanks. 

Standard OE rotors and economy brake pads. The economy pads won't eat your rotors then at tend to last longer. 

 

16 minutes ago, Florin1 said:

6. Yes I have the 3.54 gear ratio. And I turned off OD as I approached the hill anticipating it. I probably had my foot down to 80-90% throttle by the time I got to the top. 

So your choice is ditch the tires or re-gear the axles. Most that look at prices of regearing typically get shell shocked like a local gent at $4,000 for both axles and change from 3.55 to 4.11 or 4.56 for his 37" tires. Just like him he's struggling to tow anything because his final ration is 3.00:1. Towing optimal ratio for these trucks is 3.73:1 gears. Either way you need to bring your ratio back to reduce the stress on the transmission and engine. 

 

Also remember the 47RE atuo's have a final ratio of 0.68 compared to manuals of 0.75 (5 speed) or 0.73 (6 speed) ratios. Now OD OFF is the same as on gear down on manuals (1:1 direct drive). 

 

 

Edited by Mopar1973Man
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So I found a set of wheels here locally and talked lady down to DIRT CHEAP. Like $50 for all 4. Tire size is 265/70/17. Will that bring me down to a better ratio? There's about 30% left on the rubber. I like the 17" wheel idea in case I ever do upgrade to the 3rd gen brakes. I don't know the formula for figuring out that rotational size deal. 

Edited by Florin1
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