I am saddened to learn of Denny’s passing.  He was a quick wit, a kind soul, a good people leader, and most importantly a proud family man,  My deepest sympathies to Nanci and the entire Mooney family.

I am so sorry to hear about Dennis’ s passing ! My prayers and thoughts go out to the whole Mooney family ! 
Mary Brya

My deepest sympathy to the Mooney family.  Denny brought a tremendous energy and influence to the R&D community at International.  Thinking of you during this tough time.  
Ryan Ludera

Holding your hearts as you say farewell to your beloved husband, Dad, Grandpa and our friend Denny. So sorry not to be there today to celebrate his blessed life. 
He truly lived his life and faith to the fullest through his family , career and participation in his Church.  
God bless you TeamMooney (Nanci, Allison, JR and Nat plus grands ) left behind and remember us to Jesus  please Denny🙏🏻🫶🏼
Sincerely Lucy & Paddy

I met Denny in 1984 and we worked together almost 20 years. Over that period I developed a deep respect for him as an Engineer and Leader. More importantly  Sue and I enjoyed spending time with Denny, Nancy and their family.  We had great times together on and around Lake Charlevoix. We ended many days with a beer and a cocktail Looking out over the water. He was one of the best we will truly miss him!
            Tom & Sue

Nanci & family,
So very sorry for your loss.  Denny was my supervisor, a supportive colleague, and a true friend.  He will be fondly remembered.

Dear Nanci and family, our deepest condolences for your loss.  I worked with Denny way back in our younger years as development  engineers for Oldsmobile. I always remember him as such a happy, caring guy. 
He has been taken way too soon. 
We are so sorry we will miss the funeral as we will be out of the country during that time. 
Thinking of you, Joni & Jim Rainbolt

Nanci and family, 
So sorry to learn of Dennis’s passing. He was one special guy who always put a smile on my face. He will be missed by everyone who knew him. Patti and I extend our deepest condolences to you and your family.  Unfortunately we can’t be at the services, but wanted you to know we are thinking of you. 
Patti and Charley Guyselman

Hard to add just a few memories when there have been so many spread over 50 years. I shared an apartment with Denny and 2 others at Michigan for two years. Denny was always proud of our varied heritage, as our ethnicities were Syrian, Jewish, Italian, and Irish.  We didn't always agree with each other but we lived together well. We were all Americans. Prior to the apartment, Denny was across the hall from me in the dormitory, Bursley Hall.  Denny had a unique study method in those early days. He loved Hogan's Heroes, and watched episodes on tiny black and white TV, with a text book open in his lap.  He was the origin of multitasking. He also liked the 3 stooges, particularly Mo. I think Denny may have channeled Mo and Hogan effectively many times during his great career as a captain of industry. It's joyful thinking of him and painful as well.  I know we are all blessed to have known him.

Dear Mooney family, 
It is with deep sadness that I’ve learned of Denny’s passing. I worked with him in Global Engineering and for a short consultation at Navistar. I always held him in the highest regard and with deep admiration. May God bless you all in this time of mourning.

Nanci and family, so sorry to hear of Denny’s passing. His energy and sense of humor were always uplifting. His successful careers at GM and Navistar were beyond impressive. I always enjoyed seeing him when our paths crossed and will miss him.

I worked with Denny back in his early years at Oldsmobile Product Planning.  Always full of energy and excitement.  You could always count on Denny to make things happen no matter what the assignment.  Good guy, good friend from long ago.  May you all have peace in knowing how much he loved you.

I have worked with Denny ever since he joined NAVISTAR in 2008. I worked with him very closely on many projects, including the time when he led the China JV.  He was so full of energy. Besides his immense product knowledge, his natural ability to connect with people across cultures was amazing. The most impressive story was that he was able to connect with the head of the product development of the JV partner that no one can get through. After he retired, he also supported me and joined the hustle to Hancock and demonstrated his immense energy and drive by climbing 94 floors of the Hancock building in support of research for lung cancer. I will always remember his humor, energy, and love for his family. I will always be grateful for what he did for the company and for my career.

Praying today for my friend and ICAF classmate Denny and his family.   Soar with the eagles and angels pal. Watch over us and protect us as you did on this Earth.   See you on the other side when we are called to join you.

I knew Denny dating back to the early 1980s when both of us were “pups” in General Motors.  At the time, Denny worked for Oldsmobile and I worked for Buick.  But, both of us were Certification Engineers in the early days of emission and fuel economy regulations.  We had regular discussions about our favorite "workarounds" to navigate the GM and EPA bureaucracies to get approval for our new engine control systems.   We took different career paths after a few years, but both of us continued to move through the GM ranks (including international assignments) and we worked together again as senior executives for "Maximum Bob" Lutz in Global Product Development.  Denny had returned from Holden in Australia and became VP of Vehicle Engineering Systems and I was VP of the VLEs and Program Management.  It was a great to re-connect with Denny after a number of years.  Unfortunately for GM, he retired in the massive turmoil of the GM bankruptcy in 2009.  But, Denny was too young to "trade his briefcase for a hammock" and became Vice president of Global Engineering for Navistar.  Denny was a terrific guy and had a great career.

to Nanci, and all 0f Denny's family and friends, my heartfelt condolences to you for your loss of such a great person.
      I was fortunate to have worked almost 40 years with him, and several sports and civic and sports events with him, mostly over his span in Lansing's Oldsmobile Product Engineering.
     I have nothing but great memories of our frequent contacts.

Tom Erb

I had the privilege of working closely with Denny for many years. He was a wonderful colleague and I am so sad for his family!
Betsy Jackson

I knew Denny when wecOldsmobile. He was a fine man with many fine qualities. Integrity, intelligence, compassion, leadership and a sense of humor. We lost something with his passing and heaven gained something irreplaceable. Denny, I look forward to seeing you in heaven

I’m so sorry to hear of Denny’s passing but know he is at peace in heaven.  

I learned so much from him as a young leader at GM.  I use to spend a lot of time with him when I was working for Bob Lutz.  He provided me so much wisdom on how to be a servant leader and a valued peer.  I specifically remember him taking me aside after a group dinner in Korea and just spending an hour talking about life and work.   I was just  low level Technical Assistant.  He could have been spending time with his peers, instead he chose to take time helping me.  We would periodically keep in touch over the years and he even helped a good friend’s son start his engineering career at Navistar.  Rest in peace, Denny.  You made this world a better place just being you!

Nanci and the Mooney's. Love and prayers to you and your family. What a ride it was!

My sincerest condolences to Nanci and family

Denny was a classmate of mine at the Industrial College Of the Armed Forces now the Eisenhower School in Washington DC in 1998.   He was one of four civilians selected to attend our masters program as an industry fellow.

I’m a retired Naval Academy grad and former Fast Attack submarine skipper with my next tour being command. I did not know Denny the first few weeks of classes.   How we met I thought was funny so here goes.   Please be patient.

Eisenhower hall was being renovated during our first term requiring faculty and students to relocate to the Coast Guard headquarters building third and fourth floors which was a few hundred yards away.

One morning during class an Air Force Colonel sitting next to me accidentally dumped his 7Eleven 30oz ginormous mug of coffee/no lid on my summer white polyester uniform.   I fortunately was not burned but had this brown stain that covered my chest, stomach, lap and thighs.

My classmates thought it funny.  I did not.

I went to the men’s bathroom where there were 8 sinks, urinals and stalls.  I stripped down to my white socks and white uniform shoes.  I filled each sink with hot soapy water for my belt, shirt, T-shirt socks, pants and not so tidy whitey skivies.

Denny entered the men’s room saw me standing there in all my glory with a smile.   I said hi there classmate.   Denny said nothing promptly did an about face and quickly left.

After 15 min I returned to class spotless but very damp.  My classmates were shocked at the transition.  I just smirked at them.

I saw Denny later that afternoon and explained what happened.   We both had a good laugh.  What happened next was the beginning of a decades long friendship.

Last fall I called Nanci’s cell while she was visiting my friend.  I recounted the story as to how we met.  We both had grins on our faces and tears in our eyes from a good laugh.

I miss my friend and love his family.

CDR Scott D Waddle USN Ret
Lynden, WA.    USNA1981, ICAF 1998

I

Condolences to Nancy and the whole Mooney family. I grew up across the street on Cumberland Rd and spent a lot of time with Dennis and family in my younger years. I lived on Jenison street with Dennis and several other guys after college and we had many laughs and good times. I remember one Monday back at Lansing Country Club where Denny and I played 72 holes in one day.
  He was an intelligent and fun, and great guy. 
Gone too soon, but never forgotten 
Mike Maron

Denny was a great guy as both a work colleague and a friend. My thoughts and prayers go out to Nanci and the entire family. Rest in peace my friend.

Nanci,
I was fortunate to have worked with Denny at GM and of course to spend time with both of you at Hemingway.   So fortunate to have his kind and thoughtful approach to surround  all of us over the years and of course his sense of humor.   Truly an amazing person that has left a very long legacy and helped and guided so many people over the years.  Hugs to you and the family.
Mary Boland

To Nancy and all the Mooney family.My condolences.Dennis was a great person and professional.It was great to see him at the 50 th class reunion.Dennis ,Tim ,Dan , Chuck Abraham and Pat Shurmur had a great time on are Denver trip about 3 years ago going to a Denver Bronco game. It was a great time for all of us  He will be missed.Mark Farhat

Denny was always so kind to me growing up. Always a smile on his face. My deepest condolences to the family.

OBITUARY

Dennis Michael Mooney

July 11, 1956 – February 24, 2026

Gorsline Runciman Funeral Homes

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