Towing question

SuperDuper · July 27, 2021

I just picked up a new 2021 gas 2500 Sierra from Laura Buick gmc. I already screwed the pooch with the recommended break in on my drive home as I live about 400 miles away. Did a lot of 70mph driving. Did have some slower speeds mixed in, but 70 was the majority of it.

Anyways, reading the manual now I see it mentions not exceeding 50mph for the first 500 miles of towing. What’s the reasoning for this? I’m asking as I have trip coming up where I plan to tow a pontoon for about 375 miles one way. Normal driving it would take around 6 hours, so at 50 mph it will take most of a day to get there. I know break in is a hot topic with a variety of advice, so would just like to hear everyone’s thoughts. Thanks!

nards444 · July 27, 2021

7 hours ago, SuperDuper said:

I just picked up a new 2021 gas 2500 Sierra from Laura Buick gmc. I already screwed the pooch with the recommended break in on my drive home as I live about 400 miles away. Did a lot of 70mph driving. Did have some slower speeds mixed in, but 70 was the majority of it.

Anyways, reading the manual now I see it mentions not exceeding 50mph for the first 500 miles of towing. What’s the reasoning for this? I’m asking as I have trip coming up where I plan to tow a pontoon for about 375 miles one way. Normal driving it would take around 6 hours, so at 50 mph it will take most of a day to get there. I know break in is a hot topic with a variety of advice, so would just like to hear everyone’s thoughts. Thanks!

I dont know how much I believe in this break in stuff. I mean I understand giving it a few miles after purchase, double check fluids etc. Either way drive about an hour or so a night after a few nights youll be at 500 miles.

03 Cobra · July 27, 2021

8 hours ago, SuperDuper said:

I just picked up a new 2021 gas 2500 Sierra from Laura Buick gmc. I already screwed the pooch with the recommended break in on my drive home as I live about 400 miles away. Did a lot of 70mph driving. Did have some slower speeds mixed in, but 70 was the majority of it.

Anyways, reading the manual now I see it mentions not exceeding 50mph for the first 500 miles of towing. What’s the reasoning for this? I’m asking as I have trip coming up where I plan to tow a pontoon for about 375 miles one way. Normal driving it would take around 6 hours, so at 50 mph it will take most of a day to get there. I know break in is a hot topic with a variety of advice, so would just like to hear everyone’s thoughts. Thanks!

When they write the requirements for towing break in they have to consider someone towing at max capacity of the truck. Your pontoon is a few thousand pounds at most I would guess and from the truck's perspective it won't even know it's towing anything. If it was a 16k pound fifth wheel it might be different. I'd drive it and be proud!

garagerog · July 27, 2021

SuperDuper, you're fine, after all it's not like you're breaking in a new motor like Finnegan and Freiburger would. The towing restrictions probably have as much to do with bedding the brakes and breaking in the differential gears as much as the motor.

Edited July 28, 2021 by garagerog

Heavyduty SEO · July 28, 2021

On 7/27/2021 at 8:53 AM, SuperDuper said:

I just picked up a new 2021 gas 2500 Sierra from Laura Buick gmc. I already screwed the pooch with the recommended break in on my drive home as I live about 400 miles away. Did a lot of 70mph driving. Did have some slower speeds mixed in, but 70 was the majority of it.

Anyways, reading the manual now I see it mentions not exceeding 50mph for the first 500 miles of towing. What’s the reasoning for this? I’m asking as I have trip coming up where I plan to tow a pontoon for about 375 miles one way. Normal driving it would take around 6 hours, so at 50 mph it will take most of a day to get there. I know break in is a hot topic with a variety of advice, so would just like to hear everyone’s thoughts. Thanks!

first you need to read the manual you know when buy a new vehicle there are some restrictions for using it like not to over speed the vehicle and not top tow to much weight for at least first 500 to 1000 mph but nothing to worry about it just maintain it and do service on time

newdude · July 28, 2021

On 7/26/2021 at 11:53 PM, SuperDuper said:

I just picked up a new 2021 gas 2500 Sierra from Laura Buick gmc. I already screwed the pooch with the recommended break in on my drive home as I live about 400 miles away. Did a lot of 70mph driving. Did have some slower speeds mixed in, but 70 was the majority of it.

Anyways, reading the manual now I see it mentions not exceeding 50mph for the first 500 miles of towing. What’s the reasoning for this? I’m asking as I have trip coming up where I plan to tow a pontoon for about 375 miles one way. Normal driving it would take around 6 hours, so at 50 mph it will take most of a day to get there. I know break in is a hot topic with a variety of advice, so would just like to hear everyone’s thoughts. Thanks!

Real simple. The 500mi deal comes from the axle supplier AAM. AAM calls for a 500mi break in of the ring and pinions. When new, they produce a LOT of heat. Towing would compound that break in heat quite a bit hence no towing and their recommended speed no to exceed. GM applies this procedure to the break in of the truck in the manual.

AAM also calls for a fluid change at the 500mi mark to remove the stressed fluid from the break in. But of course, GM doesn't make any mention of that.

Edited July 28, 2021 by newdude

KARNUT · July 28, 2021

I guess vehicles like people are more sensitive theses days. Since the seventies I average a new truck every 2-3 years. Usually I buy one just before a long trip. Averaging 50-60K miles a year, trips come often. Half to one tons gas or diesel, stock or modified. They all had weight in them or pulled loads. In other words they worked for a living. I had one failure, a manufacturer defect. I live 20 minutes from a major highway so I guess that was the break in. Being in business and dealing with 100s of customers this was the rule not the exception. Of course they mostly drove Fords some Rams. I was the outlier driving GMs. My personal vehicle got the same treatment. Bought usually before vacation. If you have the time for the so called break in period, it can’t hurt. I don’t many who do. Never heard it making a difference.

SuperDuper · July 28, 2021

Thanks everyone for the replies so far. I'm feeling a little better about not having a bunch of towing miles on my truck before my trip. I plan to put it on my lift prior to leaving and checking the rear diff fluid and throwing some lucas gear oil in there if it has the room for it. On a side note, out of curiosity how many members on here actually adhered to the recommendations in the manual for standard truck break in and towing break in?

Random · July 28, 2021

My manual did not have anything in regards to a towing break-in period. It just states "Do not tow trailer during break-in". So for the first 500 miles no towing.

Purchased my truck before camping season started, so didn't really run into needing to worry about not towing during break-in. I tried to take back roads when I could to keep my speed below the 55 mph recommendation, but that rarely worked out the way I planned. Did "okay" at keeping it within the limits, but I didn't bend over backwards trying to meet the recommendations.

Njmurvin · July 28, 2021

My truck had 150 miles on it when I took delivery (was moved from another dealership). I had to drive about 300 miles r/t to a Camping World to get my Andersen hitch. Trying to keep the truck under 60mph on I5 was a real challenge. Another 50 miles or so driving around town before my first tow to Big Bear, CA. No problems at all pulling my 12K 5th wheel up the mountain. More importantly, the EB worked beautifully on the way down once I got the hang of using the brake to engage it.

Grjfer · July 29, 2021

14 hours ago, Heavyduty SEO said:

first you need to read the manual you know when buy a new vehicle there are some restrictions for using it like not to over speed the vehicle and not top tow to much weight for at least first 500 to 1000 mph but nothing to worry about it just maintain it and do service on time

How many Fleet buyers do you think adhere to the break-in? Contractors and repair businesses buy these new and turn them over to their Crews and off they go. Some with utility boxes loaded with tools and supplies, others towing land scape trailers or trailers loaded with building supplies. Pretty sure they are stressing the 500 mile "break in".