Over Drive

[Buster52]

I have always wondered if I put an overdrive unit on my RV will do any good. If it gives you a 10% decrease in RMPs does it give you 10% better gas mileage? Or just 2 or 3% better MPGs. Would it be worth having it done?

Thanks

[Buster52]

I always wondered about the over/under drives. I keep getting ads wanting me to buy them. Yes, I do know that you can have to high of a gear that will lug down a motor and cause it to use more fuel. This could be good for smaller rigs like the 25 to 28 footers. I just couldn't find anyone talking about it that wasn't someone wanting to sell them. And we all know that they will not tell you the downside of it. I would like to have heard from someone who has it and how it worked out. Thank for answering my question.

[Dale_Traveling]

I would pass. The real question would be how many miles of traveling would it take and potential fuel savings before the unit is paid for. Myself as a weekend/summer vacation camper racking up may be 6K miles a year I'm not sure if I would ever see the savings.

[Monaco_Montclai]

so hows driving the brick going. happy-camping

[Matt_Colie]

I would like you to temper my response with the fact that I was a multi-decade driveline engineer. There is way too little information provided to even do more than scrug. There are so many variables that even if you told me everything you do know, I could not provide a more definitive answer. So, as the consensus has said,

No.

Matt

[powderman426]

If it was helpful, don't you think the manufacturer would have added it??? Just asking.

[2oldman]

Buster52 wrote:
Would it be worth having it done?

no

[Terryallan]

Could help, could actually hurt. the higher final OD gear, Could make the engine work harder / LUG, to stay in OD. IF it does, It will not only hurt your MPG, but could damage your engine

[tempforce]

what rpm is the engine turning at 60 mph?

[poncho62]

You may get a little better mileage...not worth the cost of the upgrade, I am sure..MPG depends on a lot more than just gearing....wind resistance of an RV is a big factor

[Sully2]

You'll never save enough $$$ to pay for the OD unit

[Buster52]

I have a 1989 Southwind with a Chevy 454 and Turbo 400 trans.