Forum Discussion
APT
Aug 20, 2014Explorer
Here we are again with the gearing. The GM 6-spd has two overdrive gears. So what? It also has a first gear that is 32% shorter than GM's prior 4-spd. GM 6-spd is is similar to the 4-spd with 4.56 if you only use the first 4 gears which is done with the M trans mode. Actually, it's better because first gear is similar, gear spacing is narrower, and you probably have 5 usable towing gears instead of 4. Is 6-spd/3.72 better for towing? A little. Is Ford's Ecoboost better? Absolutely. But OP is going from a 90's Dodge gas 5.9L with very poor 4-spd gearing. The 2009 Tahoe will accelerate much better and use less fuel.

Anyway, power will not be your problem. You do need to confirm the axle ratio and HD towing package/trans cooler. Look in the glove box for a sticker with list of RPO codes. GU6 = 3.42 and K5L for the trans cooler. With those, tow rating is over 8k pounds. Payload may be exceeded well under that if you have a large family. Receiver limit at 1000 pounds is another limit typically at under 8k loaded RV.

Anyway, power will not be your problem. You do need to confirm the axle ratio and HD towing package/trans cooler. Look in the glove box for a sticker with list of RPO codes. GU6 = 3.42 and K5L for the trans cooler. With those, tow rating is over 8k pounds. Payload may be exceeded well under that if you have a large family. Receiver limit at 1000 pounds is another limit typically at under 8k loaded RV.
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