Specifications Comparison: 2005 GMC Sierra 2500 vs 2021 GMC Sierra 2500

Headroom

Trim	Eng.	Drive train	1st Row Headroom (in)	2nd Row Headroom (in)
HD 2500 Crew Cab	V8	RWD	41	39
HD 2500 Crew Cab	V8	4WD	41	39
HD 2500 Crew Cab SLE	V8	RWD	41	39
HD 2500 Crew Cab SLE	V8	4WD	41	39
HD 2500 Crew Cab SLT	V8	RWD	41	39
HD 2500 Crew Cab SLT	V8	4WD	41	39
HD 2500 Extended Cab	V8	RWD	41	38.4
HD 2500 Extended Cab	V8	4WD	41	38.4
HD 2500 Extended Cab SLE	V8	RWD	41	38.4
HD 2500 Extended Cab SLE	V8	4WD	41	38.4
HD 2500 Extended Cab SLT	V8	RWD	41	38.4
HD 2500 Extended Cab SLT	V8	4WD	41	38.4
HD 2500 Regular Cab	V8	RWD	41
HD 2500 Regular Cab	V8	4WD	41
HD 2500 Regular Cab SLE	V8	RWD	41
HD 2500 Regular Cab SLE	V8	4WD	41

Trim	Eng.	Drive train	1st Row Headroom (in)	2nd Row Headroom (in)
HD Crew Cab	6.6L V8	RWD	43	40
HD Crew Cab	6.6L V8	RWD	43	40
HD Crew Cab	6.6L V8	4WD	43	40
HD Crew Cab	6.6L V8	4WD	43	40
HD Crew Cab AT4	6.6L V8	4WD	43	40
HD Crew Cab AT4	6.6L V8	4WD	43	40
HD Crew Cab Denali	6.6L V8	4WD	43	40
HD Crew Cab Denali	6.6L V8	4WD	43	40
HD Crew Cab SLE	6.6L V8	RWD	43	40
HD Crew Cab SLE	6.6L V8	RWD	43	40
HD Crew Cab SLE	6.6L V8	4WD	43	40
HD Crew Cab SLE	6.6L V8	4WD	43	40
HD Crew Cab SLT	6.6L V8	RWD	43	40
HD Crew Cab SLT	6.6L V8	RWD	43	40
HD Crew Cab SLT	6.6L V8	4WD	43	40
HD Crew Cab SLT	6.6L V8	4WD	43	40
HD Extended Cab	6.6L V8	RWD	43	39
HD Extended Cab	6.6L V8	RWD	43	39
HD Extended Cab	6.6L V8	4WD	43	39
HD Extended Cab	6.6L V8	4WD	43	39
HD Extended Cab SLE	6.6L V8	RWD	43	39
HD Extended Cab SLE	6.6L V8	RWD	43	39
HD Extended Cab SLE	6.6L V8	4WD	43	39
HD Extended Cab SLE	6.6L V8	4WD	43	39
HD Extended Cab SLT	6.6L V8	RWD	43	39
HD Extended Cab SLT	6.6L V8	RWD	43	39
HD Extended Cab SLT	6.6L V8	4WD	43	39
HD Extended Cab SLT	6.6L V8	4WD	43	39
HD Regular Cab	6.6L V8	RWD	43
HD Regular Cab	6.6L V8	RWD	43
HD Regular Cab	6.6L V8	4WD	43
HD Regular Cab	6.6L V8	4WD	43
HD Regular Cab SLE	6.6L V8	RWD	43
HD Regular Cab SLE	6.6L V8	RWD	43
HD Regular Cab SLE	6.6L V8	4WD	43
HD Regular Cab SLE	6.6L V8	4WD	43

Trim	Eng.	Drive train	1st Row Headroom (cm)	2nd Row Headroom (cm)
HD 2500 Crew Cab	V8	RWD	104.1	99.1
HD 2500 Crew Cab	V8	4WD	104.1	99.1
HD 2500 Crew Cab SLE	V8	RWD	104.1	99.1
HD 2500 Crew Cab SLE	V8	4WD	104.1	99.1
HD 2500 Crew Cab SLT	V8	RWD	104.1	99.1
HD 2500 Crew Cab SLT	V8	4WD	104.1	99.1
HD 2500 Extended Cab	V8	RWD	104.1	97.5
HD 2500 Extended Cab	V8	4WD	104.1	97.5
HD 2500 Extended Cab SLE	V8	RWD	104.1	97.5
HD 2500 Extended Cab SLE	V8	4WD	104.1	97.5
HD 2500 Extended Cab SLT	V8	RWD	104.1	97.5
HD 2500 Extended Cab SLT	V8	4WD	104.1	97.5
HD 2500 Regular Cab	V8	RWD	104.1
HD 2500 Regular Cab	V8	4WD	104.1
HD 2500 Regular Cab SLE	V8	RWD	104.1
HD 2500 Regular Cab SLE	V8	4WD	104.1

Trim	Eng.	Drive train	1st Row Headroom (cm)	2nd Row Headroom (cm)
HD Crew Cab	6.6L V8	RWD	109	101
HD Crew Cab	6.6L V8	RWD	109	101
HD Crew Cab	6.6L V8	4WD	109	101
HD Crew Cab	6.6L V8	4WD	109	101
HD Crew Cab AT4	6.6L V8	4WD	109	101
HD Crew Cab AT4	6.6L V8	4WD	109	101
HD Crew Cab Denali	6.6L V8	4WD	109	101
HD Crew Cab Denali	6.6L V8	4WD	109	101
HD Crew Cab SLE	6.6L V8	RWD	109	101
HD Crew Cab SLE	6.6L V8	RWD	109	101
HD Crew Cab SLE	6.6L V8	4WD	109	101
HD Crew Cab SLE	6.6L V8	4WD	109	101
HD Crew Cab SLT	6.6L V8	RWD	109	101
HD Crew Cab SLT	6.6L V8	RWD	109	101
HD Crew Cab SLT	6.6L V8	4WD	109	101
HD Crew Cab SLT	6.6L V8	4WD	109	101
HD Extended Cab	6.6L V8	RWD	109	99
HD Extended Cab	6.6L V8	RWD	109	99
HD Extended Cab	6.6L V8	4WD	109	99
HD Extended Cab	6.6L V8	4WD	109	99
HD Extended Cab SLE	6.6L V8	RWD	109	99
HD Extended Cab SLE	6.6L V8	RWD	109	99
HD Extended Cab SLE	6.6L V8	4WD	109	99
HD Extended Cab SLE	6.6L V8	4WD	109	99
HD Extended Cab SLT	6.6L V8	RWD	109	99
HD Extended Cab SLT	6.6L V8	RWD	109	99
HD Extended Cab SLT	6.6L V8	4WD	109	99
HD Extended Cab SLT	6.6L V8	4WD	109	99
HD Regular Cab	6.6L V8	RWD	109
HD Regular Cab	6.6L V8	RWD	109
HD Regular Cab	6.6L V8	4WD	109
HD Regular Cab	6.6L V8	4WD	109
HD Regular Cab SLE	6.6L V8	RWD	109
HD Regular Cab SLE	6.6L V8	RWD	109
HD Regular Cab SLE	6.6L V8	4WD	109
HD Regular Cab SLE	6.6L V8	4WD	109