GM's 2020 tow rating question for all
GM as we know recently announced their '20 tow ratings which is about time they upped things. Anyways, what get's me is how their SRW can now tow 18,000. Seems odd that there can be that much of a jum...
Forum Discussion
IdaD wrote:Where have you been for the last 15 or so years?Huntindog wrote:ShinerBock wrote:LOL. True That.Cummins12V98 wrote:
What did they do??? Well they put a trans in that could handle the weight on the SAE test plain and simple.
If they had DRW trucks with the same trans that was rated to tow 23k before, then why would the trans be the weak link for a SRW to tow 18k? That doesn't make sense.
12V has a vendatta against the Allison... Has for years.
What GM did was not as simple as a beefier tranny.
In fact, if that was the case, then a simple ring and pinion swap would have allowed for a higher tow rating... That is What Ford and Ram did.
I actually had this discussion with a long time(since retired)GM employee, when the Tow ratings first started going up with the use of lower R&P ratios. I asked why GM would not put 4.10s in behind the D/A, like they do for the gas motors. He said that they tried that, and the pinion gears kept failing. Having rebuilt a few differentials, I understand the relationship between lower gears and a smaller (weaker) gear contact patch.
So why were Ford and Ram sucessful with thier trucks doing that.... This is easy. In spite of GMs lower HP and TQ, it was putting more power to the rear axle than the others.
The proof is in a couple of indisputable facts. GM was (still is?) the only one to use the SAE certified dyno testing procedure.This how they ended up with an odd (397) HP number, whereas the others always have a nice round ADVERTISEDnumber.
Further proof is GMs dominance in the many hill climb tests. This cannot happen with less power.
As for just what was done to increase the 2020 ratings. it was a multiprong approach. First the 10 speed trans allowed for the necessary gear multiplication at low/start speeds to take place in the trans instead of the rear end. They also were able to use a 3.42 (stronger) gearset instead of the 3.73s, and then they also upsized the rear end and drive shaft. Further cooling system enhancements such as redesigned oil coolers and larger fans were also used. They also beefed up the frame.
So much to 12Vs chagrin, the charge he has been making about the Allison being too weak.... Is not supported by the evidence
I think it's ridiculous to assert that any of the big three diesels dominate the others in hill climb tests. If anything it's remarkable how similar they all perform.
What I said is not an opinion, it is a fact.
GM has won just about all of them. Some were close.... Some were flat out dominating.
