leversole Posted October 23, 2010 Share Posted October 23, 2010 Let me say first I dont have the truck here yet or I could answer my own question...The truck had been listed as a triplex. When I was running the engine I noticed the shift plate (and the chassis record) say quad...on the compound stick I could not find or select LO LO, which made me think they changed the transmission when they changed the engine (to a 1973 I think ENDT675).However, it struck me this morning that maybe there is a physical lock to prevent shifting into LO-LO unless the main is in 1st? Whilst looking for LO-LO with the engine running, the main was in nuetral. Just trying to figure out if it is 15 or 18....Thanks Quote Link to comment https://www.bigmacktrucks.com/topic/16249-trq7220-question/ Share on other sites More sharing options...
Rob Posted October 23, 2010 Share Posted October 23, 2010 Let me say first I dont have the truck here yet or I could answer my own question...The truck had been listed as a triplex. When I was running the engine I noticed the shift plate (and the chassis record) say quad...on the compound stick I could not find or select LO LO, which made me think they changed the transmission when they changed the engine (to a 1973 I think ENDT675).However, it struck me this morning that maybe there is a physical lock to prevent shifting into LO-LO unless the main is in 1st? Whilst looking for LO-LO with the engine running, the main was in nuetral. Just trying to figure out if it is 15 or 18....ThanksIf you could not locate "Lo Lo" effortlessly, but can locate Lo Split, you have a triplex transmission. Could be the cab has been changed and the nameplate left in place.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment https://www.bigmacktrucks.com/topic/16249-trq7220-question/#findComment-65741 Share on other sites More sharing options...
terry Posted October 24, 2010 Share Posted October 24, 2010 Look on the left side of tranny behind the fill plug should be a flat spot with some numbers, a TRT is triplex and a TRQ is a quad. Terry Quote Link to comment https://www.bigmacktrucks.com/topic/16249-trq7220-question/#findComment-65749 Share on other sites More sharing options...
leversole Posted October 24, 2010 Author Share Posted October 24, 2010 Thanks all....I found out it is a TRTL 72...now I just need to figure out what gears it has!I assume the museum can tell me given the serial number...I have a 1961 B-61T brochure that lists the ratios for a TRTL72, just wonder if they are the same as a later model... Quote Link to comment https://www.bigmacktrucks.com/topic/16249-trq7220-question/#findComment-65752 Share on other sites More sharing options...
terry Posted October 24, 2010 Share Posted October 24, 2010 72 series is a direct tranny, a 720 is an overdrive. terry Quote Link to comment https://www.bigmacktrucks.com/topic/16249-trq7220-question/#findComment-65763 Share on other sites More sharing options...
HK Trucking Posted October 24, 2010 Share Posted October 24, 2010 72 series is a direct tranny, a 720 is an overdrive. terryThe TR72 main box is direct in hi gear, as opposed to the TR720 main box being overdrive in hi gear, but since leversole's transmission is a TRTL72, then it's a "single overdrive" triplex because hi split is overdrive in the back box. A "TRT(L) 720" would be a "double overdrive" triplex because the main box is overdrive in hi gear and the back box is also overdive in hi split. 1 Quote "If You Can't Shift It Smoothly, You Shouldn't Be Driving It" Link to comment https://www.bigmacktrucks.com/topic/16249-trq7220-question/#findComment-65768 Share on other sites More sharing options...
HK Trucking Posted October 24, 2010 Share Posted October 24, 2010 BTW, that shift pattern diagram plate in the earlier post is for a TRQ7220. Quote "If You Can't Shift It Smoothly, You Shouldn't Be Driving It" Link to comment https://www.bigmacktrucks.com/topic/16249-trq7220-question/#findComment-65770 Share on other sites More sharing options...
leversole Posted October 24, 2010 Author Share Posted October 24, 2010 The TR72 main box is direct in hi gear, as opposed to the TR720 main box being overdrive in hi gear, but since leversole's transmission is a TRTL72, then it's a "single overdrive" triplex because hi split is overdrive in the back box. A "TRT(L) 720" would be a "double overdrive" triplex because the main box is overdrive in hi gear and the back box is also overdive in hi split.All good info! Thanks... This goes along with the ratios listed for the TRTL 72 in my only B-61 brochure which lists 5Direct as 1.00 and .85 ratio for 5 Hi Split.Would the others be the same same ratios for all years of the same model transmission?Thanks All Quote Link to comment https://www.bigmacktrucks.com/topic/16249-trq7220-question/#findComment-65779 Share on other sites More sharing options...
b68 Posted March 14, 2016 Share Posted March 14, 2016 On 10/24/2010 at 8:33 AM, HK Trucking said: BTW, that shift pattern diagram plate in the earlier post is for a TRQ7220. Quote Link to comment https://www.bigmacktrucks.com/topic/16249-trq7220-question/#findComment-327485 Share on other sites More sharing options...
b68 Posted March 14, 2016 Share Posted March 14, 2016 If you're not going to use that shirt paternity tag I'd like to buy it. Quote Link to comment https://www.bigmacktrucks.com/topic/16249-trq7220-question/#findComment-327486 Share on other sites More sharing options...
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