Comparisons Between the Rolex GMT and GMT II Models

[springer]

What follows is a quick tutorial for the novice collector comparing the attributes of the GMT 1675, 16750 and 16700 and the GMT II 16760 and 16710 models. While not all encompassing, the following should provide a basic understanding of the various GMT and GMT II models and offer the reader the opportunity to do additional research on these models. (Pricing information for the various GMT models mentioned within each section is based on current market trends as of October 2017.)

GMT 1675

The GMT model was introduced during 1959 as a replacement for the first generation GMT 6542. This new model became the workhorse for pilots, astronauts and other enthusiasts that felt the need for a watch that was capable of simultaneously keeping time in two separate time zones with just a glance at the dial. This workhorse remained in the Rolex lineup until 1979 when it was discontinued and replaced by the GMT 16750. The first generation of GMT 1675s are distinguished from the later 1675 versions by their glossy gilt or gold-colored dial fonts and markings as well as their unique, pointed crown guards which appeared similar to a “bird’s beak.” The pointed crown guard case was eventually replaced around 1963 with a more conventional, rounded, crown guard case that continued in use with all subsequent GMT and GMT II models. Interestingly, the gilt dials continued in production until 1966 with the newer, rounded, crown guard case. After this time, the gilt dials were permanently replaced with a matte black dial with white fonts and markings which marked a new era for the GMTs.

There were a couple different movements utilized during the 1675's 21-year production run. The caliber 1565 (marked 1560 on the auto winder bridge) was utilized through the gilt-dial era and was replaced around 1965 with the caliber 1575 (marked 1570 on the auto winder bridge). The caliber 1575 was the last movement used in the 1675s until the end of production in 1979. The 1565 and early 1575 movements did not have a hacking feature – a function that allowed the movement to be fully stopped by pulling out the winding crown to its outermost position. During the early 1970s, a hacking feature was added to the caliber 1575 movement which was found on all subsequent GMT movements.

Another distinguishing feature of the GMT 1675 are the dial hands. While consisting of four hands, the unique, red, 24-hour hand came in two variations. On both the original GMT 6542 and early 1675s, the 24-hour hand had a small triangle pointer at the end of the hand. This smaller version of the 24-hour hand was used throughout the complete 1675 gilt-dial era and is also found on some of the early white-lettered dials. Once the smaller hand was discontinued, it was replaced by a visually larger triangle pointer 24-hour hand which was found on all subsequent GMT and GMT II models.

The GMT 1675 models utilized an acrylic (plastic) cyclope crystal which Rolex parts books identified as the Cyclope 116. There was an additional tropic crystal without a cyclope available for purchase from dealers or the Rolex Service Centers which was referred to as the Tropic 38.

Both the GMT 1675 and 16750 utilized the same bezel assembly which was rotated by applying downward pressure to the bezel. It was capable of rotating in either direction and did not have any type of click-stop feature like that found on the later sapphire crystal GMTs. The bezel inserts were initially red and blue and referred to as "Pepsi" inserts due to the similarity in colors found on the Pepsi logo. Later, sometime during the mid to later 1970s, a solid black bezel insert was added as an option for the 1675 model. (The GMT 1675 never came with a bezel insert in the red/black color combination. This color combo would not find its way on to a GMT until 1983 with the introduction of the GMT II 16760 then later on the GMT II 16710.)

The GMT 1675 was fit with a few Oyster bracelet variations during its time as well as a Jubilee bracelet option. Oyster bracelets included the Swiss-made 7206 rivet (with 58 end links) which was utilized through the 1960s and later replaced by the Oyster 7836 folded-link bracelet around 1970 which was replaced by the 78360 Oyster bracelet sometime around 1976/77. There was also a stretch, or spring-link, version of the rivet Swiss-made Oyster bracelet available, model 6636 with 58 end links, that was available during the same period as the Oyster 7206. The Swiss manufactured Jubilee bracelet used on the GMT 1675 was the 6251 model with 50 stamped end links with the stamping on the right ear of the end link. This bracelet had folded links when viewed from the side and appeared to have an "unfinished" look. Later, during the late 1970s, the 6251 Jubilee would be replaced by the Swiss-made Jubilee 62510 which had solid "D" shaped links when viewed from the side. The last links on the 62510 models were stamped with the number 50 while the end links were stamped 550. The Swiss bracelets are normally found with a date stamping on the outer clasp blade.

There were also USA manufactured Oyster and Jubilee bracelets available in the United States for the GMT 1675s found on both the stainless steel and two-tone models. These bracelets included the USA C&I Oyster rivet bracelet used during the 1960s until it was discontinued around 1978 or 1979 along with the USA made oval-link Jubilee bracelet used during the same time period. The C&I Oyster bracelets did not contain end link numbers or a model number but did have dated clasps. The USA Jubilees are normally not found with date stamps on the clasps but occasionally you will find one with a date stamp which is not a common occurrence. The USA Jubilees are not normally found with end link numbers except that you will occasionally find them with a 50 stamp on the left ear of the end link. (These 50 stamped end links found on the USA Jubilees are rather sporadic and, again, not common. They could have possibly been used during the 1960s which is where this end link/bracelet combination seems to be the most prevalent.)

The GMT 1675 was discontinued during 1979 when it was replaced by the GMT 16750. Today, the GMT 1675s are as popular as ever among collectors with strong demand for excellent to superior examples. Collectors should expect to pay $10,000 or more for excellent examples of the white-lettered, non-gilt, models. Excellent examples include watches with correct parts - such as period correct bezel inserts, dials, bracelets, hands etc. Those found with dial patina or with cases in superior condition bring premiums and can be found selling for prices exceeding $12,000 to $14,000. Complete sets sell for substantially more with premiums as high as 50% or more.

The gilt-dialed GMTs sell for much more than their white-lettered counterparts. Pricing is heavily predicated on watch and dial condition. Prices for these models are $20,000 plus for correct, complete watches in excellent condition.

GMT 16750

With the introduction of the matte dial GMT 16750 during late 1979, this new model retained many similarities and interchangeability with the previous 1675 model - to include the same acrylic (plastic) crystal, same case dimensions, case back, bezel assembly, bezel inserts and a matte dial. While both the 1675 and 16750 shared many similarities, the dials and hands are not interchangeable between these two models.

The movement was changed to the caliber 3075 for the GMT 16750 with the most significant aspect of this movement having a true, quick-set date feature which many collectors enjoy. Due to this new movement, the hands have the same appearance as those found on the earlier GMT 1675s, but the hand stack changed with the new movement - now having the hour hand on the bottom of the stack unlike the GMT 1675 where the 24-hour hand was at the bottom of the hand stack.

The early 16750s came with matte dials like those found on the GMT 1675 models. The 16750 models would use the matte dials until approximately 1984 when the dials were changed to a glossy finish with white gold surround markers. This is not to say that you can't find one earlier than 1984 since I have seen several with a serial number as early as 8.2XXXXX (circa 1983) while others, both on TRF (rolexforums.com) and elsewhere, have owned glossy dial versions with even earlier serial numbers. The glossy dial on the very early GMT 16750 is unique when compared to the later glossy dials. What makes this early glossy dial unique is the absence of the word "DATE" found within the dial phrase OYSTER PERPETUAL DATE. These early glossy dial versions are often called "no date" models which does not refer to the absence of a date wheel, but instead, refers to the absence of the word "DATE" from the "OYSTER PERPETUAL DATE" phrase found on the later glossy dials. (Note: All of the 16750 and 1675 matte dials contained the dial verbiage "OYSTER PERPETUAL" and none contained the late "OYSTER PERPETUAL DATE" verbiage as found on the later, glossy 16750 dials except for some of the very early glossy 16750 dials.)

The GMT 16750 model used the same acrylic crystals as found on the GMT 1675 – the standard Cyclope 116 and the optional Tropic 38 (without a cyclope) which was available from dealers or the Rolex Service Centers.

The GMT 16750 used the same bezel assembly as the GMT 1675 which was rotated by applying downward pressure to the bezel. It would rotate in either direction and did not have a click-stop feature like that found on the later sapphire crystal GMT models. The inserts remained the same as those found on the later GMT 1675s - retaining both the solid black and the red/blue "Pepsi."

The 24-hour red hand remained fixed on both the GMT 1675 and 16750 models and could not be set independently. Reading secondary time zones remained a function of the bezel/bezel insert which was rotated to align with the 24-hour hand to read a secondary time zone.

The GMT 16750 can be found with serial numbers as early as 6.1 million. It continued in production until approximately 1988 when it was replaced by the GMT 16700 model which had a sapphire crystal and a new movement - the caliber 3175. Matte-dialed examples of the 16750 are limited in the market due to a short production period of only four to five years before the changeover to the 16750 glossy dials in 1984.

The GMT 16750 matte dial watches are very popular among collectors due to its similar appearance to the GMT 1675 and its quick-set date function. The demand for quality, matte-dial examples is very strong – especially for those in correct, original, excellent condition. Quality examples sell for $10,000 on up with complete, sets bringing premiums of 40% to 50%. Watches found with minimal polishing, dial patina and/or to be in superior condition bring premiums and can be found selling for even higher prices.

The glossy dial variation of the GMT 16750 are also fine examples of vintage GMTs. Although not as pricey as the matte dial counterparts, collectors are finally starting to warm up to the glossy dial GMTs more every year. Nice examples can be found in the $6,500-$7500 range and higher, with sets bringing 20%-30% premium.

GMT II 16760, aka The Fat Lady

During 1983, the first GMT-MASTER II, model 16760, was introduced. It had a sapphire crystal, a glossy black dial and a new movement, the caliber 3185, which operated a little differently than previous GMT movements. The 16760 is often referred to as “The Fat Lady” due to a significantly thicker case than found on previous GMT models. (Once the 16760 was discontinued, the case was slimmed back down for the subsequent GMT 16700 and the GMT II 16710 models.)

A new feature and a first for the GMT models was the addition of an independent-moving hour hand found within the caliber 3085's movement. This feature allowed the hour hand to be set independently without disturbing the other hands. This same feature also allowed for quick rotations of the hour hand for setting the date which alluded to it being called a semi, quick-set date function instead of being a true quick-set date feature as found on the GMT 16750 and 16700. (This same, independent, hour hand feature would later be found on the GMT II 16710 but not the GMT 16700.)

The 16760 came with only one bezel insert option which was black and red in color - often referred to as the "Coke" insert due to its colors resembling the Coca Cola logo. Another first for the GMTs found with this model was the newly introduced rotating bezel which would later be found on the GMT II 16710 and GMT 16700 models. This new bezel had a click-stop ratcheting feature which allowed the bezel more ease of movement, either forward or backward, when compared to the previous GMT 1675/16750 bezels. Both the bezel and bezel inserts found on the 16760 are interchangeable with the GMT II 16710 and the GMT 16700.

The hand stack remained the same as found on the GMT 16750 with the hour hand on the bottom, followed by the 24-hour hand, minute hand and seconds hand.

Available bracelets were the Oyster 78360 (with 501 end links) and 93150 (with 593 end links), as well as the Jubilee 62510 (with 502 end links).

Production of the GMT II 16760 ended during 1988 when it was replaced by the GMT II 16710.

Current prices for nice examples of the GMT II 16760 can be found from $6,500 to $7,500 with a 40%-50% premium placed on complete sets. As with all vintage watches, the pricing quoted here is a guide - with finer examples selling at premiums.

GMT II 16710

After the GMT II 16760 was discontinued during 1988, it was replaced by the GMT II 16710 which continued in production until it was discontinued during 2007. While the changes to this model were minor when compared to the previous 16760, the most significant visible change was the case size. The 16710 case was reduced in size from the 16760 - with the 16710 having a noticeably thinner case.(Visually, the 16710 case and GMT 16700 case appear similar in size.) A new movement was introduced with the 16710 – the caliber 3185. This movement functioned primarily the same as the caliber 3085 which it replaced. It shared the same, semi-quick set date function as well as an independent-moving hour hand as the 3085 movement. Toward the end of the production run of the 16710s, the movement was replaced by the caliber 3186 which contained a different hairspring assembly than the 3185.

During 2004, with the introduction of the “F” serial numbers, the GMT II 16710 case was redesigned to eliminate the use of visible spring bar holes in the lugs. These revised models offered a nice, clean look to the case lugs. The bracelets for these models had notched end links for removing the spring bars. The end links were now permanently attached to the bracelet. The most common bracelets found on these later models after 2004 were the Oyster 78790A and Jubilee 62510.

The red and blue "Pepsi" inserts returned with the GMT II 16710 models after being noticeably absent from the previous GMT II 16760. Also available were two other bezel insert options - solid black and the red/black "Coke" carryover from the previous 16760. The bezel, with its ratcheting click-stop feature, is the same as found on the GMT II 16760 and GMT 16700 which is interchangeable between these three models.

The 16710s were available with several bracelet options during its nearly 20-year run. Oyster bracelets available with removable end links were the 78360 (later replaced by the 78790), 78790A, 93150 and the Jubilee 62510 which also had removable end links. Later, solid, non-removable end links were added to the Oyster 78790A bracelets.

All the dials for the 16710 were glossy black with white gold surround markers with tritium phosphorescence marked SWISS - T<25. Beginning around 1998, for a year or two, the phosphorescence was changed to luminova. These luminova dials are easily discernible by the absence of the SWISS - T<25 printing at the bottom of the dial which was replaced by the word SWISS. The luminova dials were subsequently replaced around 1999 with super-luminova dials which were marked SWISS MADE at the bottom of the dials. Once the change-over occurred, the super-luminova dials would be the only dials used on the 16710 until the end of production.

Current prices for nice, superior examples range from $6,500 to $7500. Complete sets seem to range from $7,000 to $8500, depending on condition and originality. Again, as with all GMTs, prices are based on rarity and condition, condition, condition.

GMT 16700

The GMT 16700 replaced the GMT 16750 during 1988 and was produced until 1998 with the "A" serial numbers. This model retained many of the same features as the previous GMT 16750 model with the exception of it now having a sapphire crystal and a new movement – the caliber 3175. The 16700 movement utilized the same quick-set date function as found on the 16750. Visually, the case was similar in size and appearance to the GMT 16750 and GMT II 16710.

There were two bezel inserts available on this model - solid black or the red/blue "Pepsi." Noticeably absent as a bezel insert option for the GMT 16700 was the red/black "Coke" insert. (The Coke insert would later return and become an option on the GMT II 16710.) The rotating bezel was the same as found on the GMT II 16760 and 16710 models with its ratcheting click-stops and ability to move in either direction. The bezel and bezel inserts from the GMT 16700 are interchangeable with both of the GMT II models.

All the dials for the 16700 were glossy black with white gold surround markers with tritium phosphorescence marked SWISS - T<25 at the bottom of the dial. During the last year or two of production, the phosphorescence was changed to luminova. These luminova dials are easily discernible by the absence of the SWISS - T<25 printing on the dial. Once this changeover occurred, the dials would now read SWISS at the bottom of the dial.

During the GMT 16700's production years, it was made alongside the GMT II 16710 for approximately 10 years. While production of the GMT 16700 would end around 1998, the GMT II 16710 would continue in production until 2007.

GMT 16700 pricing seems to follow the pricing pattern of the GMT II 16710 even though the GMT 16700 was made in much lesser quantities.

GMT and GMT II Movements:

GMT 1675: 1565 (marked 1560 on the bridge, replaced by caliber 1575 around 1965)
GMT 1675: 1575 (marked 1570 on the bridge - hacking feature added during early 1970s)
GMT 16750: 3075 (with quick-set date setting function)
GMT 16700: 3175 (replaced the GMT 16750 with quick-set date setting function)
GMT II 16760: 3085 (semi quick-set date setting function with independent hour hand)
GMT II 16710: 3185 (semi quick-set date setting function with independent hour hand)
GMT II 16710: 3186 (semi quick-set date setting function with independent hour hand. Found in the GMT II during
the last year or two of production. )

PRICING

Pricing comments provided here are a guide and as mentioned in the first paragraph from this thread, pricing was indicative of watches found during the fall of 2017. Many factors should be considered when buying a vintage GMT/GMT II, to include: dial condition, case condition, originality of parts, bracelet condition, bezel inserts and accessories - especially when considering the purchase of a set. Unpolished watches seem to bring a slight premium, especially those found in excellent to superior condition.

[leefowler]

Awesome post, very informative. Thanks