Exhibit 10.21

LOGO [g152521gmacforex10_20-24pg1.jpg]

GMAC Inc.

200 Renaissance Center, M/C482-B14-D46, Detroit, MI. 48265

March 25, 2010

James Mackey

Re: GMAC Inc. Deferred Stock Units

Dear Jim:

As a result of a recent determination from the Office of the Special Master for
TARP Executive Compensation, effective January 1, 2010 (the “Investment Date”),
a portion of your annualized 2010 cash compensation, $1,000,000, will be
deferred and invested in Deferred Stock Units (DSU”s) as described below.

This form of compensation remains subject to revision at any time in order to
comply with any Federal law or regulation that may govern executive
compensation, including but not limited to Title VII of the American Recovery
and Reinvestment Act of 2009, the Interim final Rules issued pursuant to this
law, and the Troubled Asset Relief Program (collectively the “TARP Rules”).
Additionally, the components of your total compensation, as well as the
allocation of your total compensation among the various components may be
prospectively adjusted at any time at GMAC’s sole discretion.

The value a DSU on the Investment Date will be based on the value of a
Restricted Stock Unit on the Investment Date (as defined in the Long Term Equity
Compensation Incentive Plan or “LTECIP”). The value at the time of any payment
(“Settlement Date”) may differ, depending upon increases or decreases in GMAC’s
value, as well as adjustments for recapitalization, merger, etc. as outlined in
Section 6.2 of the LTECIP.

Unless otherwise specified in any plan document, DSUs will not determine any
potential severance you may become eligible for. Rather, severance under any
applicable plan will be determined based only upon your direct cash compensation
in effect prior to the date of this letter.

Subject to requirements of any Federal laws or regulations that may govern
executive compensation, including but not limited to the TARP Rules, settlement
of your DSUs will be made as follows with each occurrence constituting a
“Settlement Date”:

 

  •  

For  1/5 of each investment, on the first payroll following a date 12 months
from Investment Date

 

  •  

For  1/5 of each investment, on the first payroll following a date 24 months
from Investment Date

 

  •  

For  1/5 of each investment, on the first payroll following a date 36 months
from Investment Date

 

  •  

For  1/5 of each investment, on the first payroll following a date 48 months
from Investment Date

 

  •  

For  1/5 of each investment, on the first payroll following a date 60 months
from Investment Date

These payments are not subject to forfeiture and will be made pursuant to this
Settlement schedule, regardless of your employment status.

Additionally, to the extent that you received 2009 DSUs, pursuant to a recent
determination from the Office of the Special Master for TARP Executive
Compensation, your 2009 DSUs will settle on the same payment schedule as
described above for 2010 DSUs. By signing below, you acknowledge and agree to
this revised settlement schedule for any 2009 DSUs.

 

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James Mackey

March 25, 2010

 

By signing below, you acknowledge your understanding that your DSUs are subject
to the rules under Code Section 409A, and you agree and accept all risks
(including increased taxes and penalties) resulting from Code Section 409A. In
order to receive these DSUs, your signature is required no later than April 2,
2010. Please return the signed copy to Nancy Bechtel; Nancy.Bechtel@gmacfs.com;
Phone (313) 656-3857.

 

Sincerely yours, LOGO [g152521gmacforex10_20-24pg2.jpg] Anthony S. Marino GMAC
Group VP and Chief HR Officer March 25, 2010

 

/s/ James Mackey

   

March 25, 2010

Signature     Date

 

    GMAC ID * (Required)    

I HEREBY DESIGNATE THE FOLLOWING BENEFICIARY TO RECEIVE ANY PAYMENTS SUBSEQUENT
TO MY DEATH.

 

 

   

 

Beneficiary Name     Social Security Number

 

* Your six-digit ID used to log into Exchange

 

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