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**jocko** · 03-16-2017, 10:02 AM

No need to swap rear gears just because of the trans swap. Both current trans and TH350 have 1:1 highway gear, so mileage and rpm should be the same. 350/TH350 probably the most common swap ever, tried and true - am sure many on here can help with the rest of your details. Having said all that, if you haven't already procured the trans, might want to consider an overdrive trans to reduce highway rpm and maybe gain a few mpg - now would be the time to do it. All budget dependent, of course, but just a consideration.

03-16-2017, 10:02 AM	#2
jocko Senior Member Join Date: Oct 2009 Location: Godley, TX Posts: 17,933	Re: Engine and trans No need to swap rear gears just because of the trans swap. Both current trans and TH350 have 1:1 highway gear, so mileage and rpm should be the same. 350/TH350 probably the most common swap ever, tried and true - am sure many on here can help with the rest of your details. Having said all that, if you haven't already procured the trans, might want to consider an overdrive trans to reduce highway rpm and maybe gain a few mpg - now would be the time to do it. All budget dependent, of course, but just a consideration.