I have a few questions about two major purchases I'm about to make.

I'm getting ready to buy a Tahoe (~$43,000), and according to the dealer, I should qualify for 0% (Exp - 673, TU - 713, Equ - 738). I don't want to jeapordize getting a good rate for my home loan, which I should be locking sometime in July-September. I have good debt/income already, so I don't think the vehicle purchase should have too much of an impact. What do you think?

Also, based on my scores, is 0% from GMAC likely?

Finally - should I get pre-approval from GMAC? Will that result in one or more "hard pulls"?

I am reluctant to answer any question to jeopardize your home loan.
I would recommend you wait till you have the keys in your hand after you close.

Once you sign the papers at closing, and if you can wait to move, go and buy the tahoe.. ONLY after signing all the docs at CLOSING FIRST!

x2

And GMAC pulls EX in my area, not sure about yours.

I would wait until after the loan is funded & deed records. I have a relative in the RE business and he tells me how many previously qualified home buyers that don't qualify for the house bought when they bought the car before the deed records.

I would guess that they will have many more incentives on the Tahoe due to the very soft market of SUV's. After the house closes, shop around & get the best deal on the Tahoe.

Please wait on buying your tahoe. This quote above would have been ok three years ago. It doesn't fly too well in this economy. They might see it as even riskier. Put yourself in their shoes, they might be askign themselves, "what if she loses her job or takes a paycut?".

HOLD ON IT!