Towing with a new vehicle

[Flybob]

Originally Posted by PenJoe

The only problem we have had with the truck to date was a parasitic draw caused by a dome light circuit. .

Do you have more info on this. I have a draw in my 2015 I have been chasing.

[ProfChuck]

Originally Posted by woodrockin

Traverse City?

Yes, Got it at Bill Marsh. Had to find a local dealer when we got back and surveyed the area, settling on Bradley GMC. Mr. Bradley died and the dealership changed hands and service deteriorated, so we switched to a LaFontaine Chevrolet dealership close by, since they also had GMC service. LaFontain later bought the Bradley (replacement) dealer out as well, but, we have continued with the Chevrolet dealership owned by LaFontaine, since we have established a repore with them - and they are closer. One other thing we do is use a product called "Motor Kote" in all our engines. Our cars are all over 230,000 miles and still don't burn oil. Before that, best I could do was about 180,000 miles before oil burning became a problem. We keep our cars up to about 350,000 miles as long as they don't rust out.

[ProfChuck]

Originally Posted by BigH

Would you start your cold motor, put it in gear and drive the crap out of it before it warmed up? If you answered yes...you are a fool. Motor manufacturer's do this to increase wear for testing purposes. They will perform this x many times, disassemble the motor and check wear to represent what happens over time and also to make sure it will stand up to people I named in the second sentence on this post.

Metals (alloys) change shape as they change temp. Dissimilar metals in tight spaces change shape and temperature at different rates. This changes clearances and can cause hot spots where parts touch or nearly touch. I check the valve clearances on my motorcycles and have for years. The motors have to be at room temp and you are looking for tolerances that span .0027 -that's minimum to maximum on the bike I did the other day. If below that minimum you are in danger of destruction.

So how does that pertain to break-in and why a 'second' break-in when towing for the first 'x' miles. Metallurgy and machining have improved a great deal but this does not change what is described above...different alloys expand, contract, change shape and transfer heat at different rates. Therefore changing speed and load early is beneficial in moderation. When towing you are increasing the load (heat) on these parts again. Your temp gauge may not move but you are definitely making more heat on your tight tolerance parts inside your motor (and rear end).

I write cnc programs and machine fine tolerance parts. Fine tolerance parts have clearances that are decided by what material (or alloy) and operating temp.

My generators at work are plugged in and kept very warm with heaters (even the gen that is inside)...this is about maintaining clearances and keeping the oil warm. -For longevity.

Is your motor going to explode if you ignore the manual and follow someone's theory on the interwebs...not likely, the manufacturer's test for you. You are certainly providing the best odds for longevity with a proper break-in and letting your vehicle warm up before putting the hammer down.

As you can see by my previous post I certainly agree with the above post!

[BigH]

Originally Posted by ProfChuck

As you can see by my previous post I certainly agree with the above post!

Why some folks place effort into justifications to not follow the break-in procedure as stated by the vehicle manufacturer is beyond me... .

[mwdilday]

When I bought my 2017 Ford 6.7 diesel the manual said no towing first 1,000 miles. We were on our way from Myrtle Beach to Washington DC and had truck issues with my 2002 F-250 so decided to stop by home and buy a new one. Needless to say we were headed to DC pulling the trailer and really didn't want to stay at the unplanned stop too long. Asked the service manager and he said hook it up and go. No break-in for us. Towing a 9,000 trailer.

[PenJoe]

Originally Posted by Flybob

Do you have more info on this. I have a draw in my 2015 I have been chasing.

As stated prior, the '13 Silverado went between 2 dealers and the shop that installed the head unit. Two Chevy techs in two different states said there was nothing wrong. Though I did not have a lot of confidence in the after market shop, he did take me out to the shop, showed he had completely disconnected the head unit and there was parasitic draw in excess of the norm. It was always the other guy's problem. It was like people trying to give directions and each pointing another direction. With no solution, we decided to live with it

I did a lot of research and excessive parasitic draw is not uncommon with many vehicles. It is more common when after market accessories are added. The problem is, it may not always be the same culprit, so no common cure.

Our dome lights, as yours, stay on for a period of time, then fade off. They were acting "normally". At some point, I turned the interior lights off, don't even recall when or why. For some reason, we didn't start the truck for several days. We were resolute that we would have to jump start. But, no, it started right up. Since disabling the dome lights, no problem in over two years. We still have the original battery from 2013. Since we don't need the interior lights when we exit the vehicle, we have not bothered to find the fault in that circuit.

But here is what I did find on YouTube. There may be main fuses under the hood, Those may go to another fuse block in the dash that fans out to other circuits. The parasitic draw is insufficient to cause cause either fuse to blow, but enough to drain the battery in a matter of hours. The alternator will recharge the battery if the vehicle is run often enough.

Parasitic draw can be determined by to two methods. Note, there will be minimal draw on some and that is normal. Either may eventually require a schematic for the affected circuit.

1. Place a volt meter between the negative battery terminal and the disconnected negative cable. Then, removing a fuse at a time, watch for a small voltage drop. If you find one, check them all. There may be another.

2. Use the amp meter. Pull each fuse and check for a excessive amp draw with the fuse removed one-by-one. Once you have determined which circuit, it is a matter of finding it down stream. Most often, it is a stuck relay in the circuit or something like a defective amp in the radio. The relays are most often in the main fuse block.

3. At times the charging circuit can actually be the culprit. But I would be looking for the most likely first. Or, it could be the battery.

By what I have recently learned trouble shooting another vehicle, my problem is hopefully a relay. Fairly inexpensive plug and play.

If you have not already done so, go on line and type " 2015 Chevrolet Silverado parasitic draw". You can also check Sierra as it is the same.

You may get lucky. Let us know how you come out.

[TT233S]

Originally Posted by BigH

Would you start your cold motor, put it in gear and drive the crap out of it before it warmed up? If you answered yes...you are a fool.

This is the best way to get my ATV's going

[Hersbird]

You guys are all missing the question. According to the OP you need to not exceed 50 mph for the first 500 miles of TOWING. The truck could already have 50,000 miles on it and never towed anything and according to the book you have to keep it under 50 mph for that first 500 miles that you are towing. That's just BS lawyer talk trying to cover their butts in case of a defect or poor assembly in the hitch.

[BigH]

Originally Posted by TT233S

This is the best way to get my ATV's going

None of mine ever required that kind of abuse (carbed or fuel injected)...

Originally Posted by Hersbird

You guys are all missing the question. According to the OP you need to not exceed 50 mph for the first 500 miles of TOWING.

No...I covered it.

The truck could already have 50,000 miles on it and never towed anything and according to the book you have to keep it under 50 mph for that first 500 miles that you are towing. That's just BS lawyer talk trying to cover their butts in case of a defect or poor assembly in the hitch.

Yep that's what the manual says and no defect by a manufacturer will negate any legal ramifications for poor assembly/under designed 'parts'/or whatever because they 'recommend' not exceeding 'x' mph for 'x' miles.

Now, will a motor with 50,000 miles put under a sustained load for the first time benefit from following the manual. Yes it will for the reasons I stated in a previous post but for sure being considerate during the earlier miles would have more impact.

[doulos]

Do whatever you think you can afford. Personally I’d follow the manual.

[Texas]

Do you really want to consider opinions over the manufacturer’s requirements?

[rasi54]

The first 500 miles are to properly break in the rear differential - pinion and ring without a heavy load

[Azdigs]

Originally Posted by dseepersad

So, we just purchased a new tow vehicle...2018 Chevy Silverado 1500 with 5.3L V8 and 3.42 rear axle ratio and tow package (not max tow package).

We know it will have no problem towing our 21SS.

My question is: I was reading the manual trying to figure something out and looked at the section on towing; it says no towing for the first 500 miles (no problem) but then it says, when you are towing not to exceed 50 mph for the first 500 miles of towing.

My husband can't believe this is true.

Thoughts? Opinions?

Although they may not refer to the reason in the book, most vehicles need to correctly seat, or break in, the differential correctly. This process helps reduce future problems. Those large mining trucks are a perfect example. They post a very precise detailed section in the Operating & Maintenance Manual on what the load limits are to break in the diff correctly. Passenger vehicles like what we tow with, obviously don’t haul the tonnage those big mine trucks do but we should follow the recommendations in the manual to make sure we do no damage.

[wannabeowner]

Personally, I'd go with the manual. On your 70 mile trip, traveling at 50 mph will probably add somewhere between 15 and 20 minutes to your trip. If you've got the stock tires*, their max speed rating is only 65 mph so you probably ought not run those at max speed anyway, that means the difference between 60 and 50 mph is only about 15 minutes. Seems to me like a small sacrifice - just in case it makes a difference for the differential over the life of your truck.

*Stock tires on your TT.

[Wicked Ace]

Originally Posted by Azdigs

Although they may not refer to the reason in the book, most vehicles need to correctly seat, or break in, the differential correctly. This process helps reduce future problems. Those large mining trucks are a perfect example. They post a very precise detailed section in the Operating & Maintenance Manual on what the load limits are to break in the diff correctly. Passenger vehicles like what we tow with, obviously don’t haul the tonnage those big mine trucks do but we should follow the recommendations in the manual to make sure we do no damage.

The engine, differential and transmission need to wear in. The 50 MPH requirement is probably to force the transmission to shift more frequently, vary the engine rev range and vary the load on the rear. This is a high friction time for those components. OR they just want to really inconvenience you and P*$$ you off. The ones who tell you to change the oil after 500 or 1000 miles are talking out their blow holes too. In the end it's your truck now so do with it as you like.

[Matster]

You're possibly over reading it... I read it as not exceeding 50mph the very first 500 miles of towing, not on every time you tow...

[dseepersad]

Originally Posted by Matster

You're possibly over reading it... I read it as not exceeding 50mph the very first 500 miles of towing, not on every time you tow...

That is how I read it too. But, it will take us around 4 round trips on a major interstate to our campground of choice before we hit 500 miles of towing.

We do plan to take it easy for that first 500 towing miles though.

[5er_tom]

I would not worry about it. Just drive safe and sane. When my truck self destructed in WV I had no choice but to replace it and move on. So with ~~100 miles on the new one we hooked up the 12,500# 5er and off we went.
Folks here on the forum said it is mainly the rear end gears that need the break in period. At my first oil change (7,500 miles) I had the Ford dealer check the differential fluid. The fluid was clean, no burn smell and no metal.
So, fly, be free.

[JohnD10]

When you take something out of the microwave oven after 10 minutes on high and the box said "Allow to cool for five (5) minutes"...

Should you ignore that warning and take a great big bite right away?

[acadianbob]

It DOES make a difference for your rear differential. That is what is being broken in; not so much the engine.