Please read the following table in HTML format from a webpage and then answer the question in detail according to the table. Each table cell is defined by a <td> and a </td> tag. Each table row starts with a <tr> and ends with a </tr> tag. 'rowspan=m' and 'colspan=n' represents a cell spaning over 'm' rows and 'n' columns.

Webpage title:
Gillig Transit Coach School Bus
Table title:
Powertrain
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Engine </th><th colspan=1 rowspan=1 > Configuration </th><th colspan=1 rowspan=1 > Production </th><th colspan=1 rowspan=1 > Gillig model code </th><th colspan=1 rowspan=1 > Engine fitment </th><th colspan=1 rowspan=1 > Notes </th><th colspan=1 rowspan=1 > Transmission </th></tr>
<tr> <th colspan=6 rowspan=1 > Diesel engines </th><td colspan=1 rowspan=11 > Spicer 6252 5-speed manual Fuller T905 5-speed manual Fuller RT610 10-speed manual Allison MT643 4-speed automatic Allison MT644 4-speed automatic Allison HT740 4-speed automatic </td></tr>
<tr> <td colspan=1 rowspan=1 > Caterpillar 1160 Caterpillar 3208 </td><td colspan=1 rowspan=1 > 636 cu in (10.4 L) V8 636 cu in (10.4 L) turbocharged V8 </td><td colspan=1 rowspan=1 > 1970-1982 </td><td colspan=1 rowspan=1 > 636D </td><td colspan=1 rowspan=1 > Rear </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > Cummins C-160 C-170 C-180 C-190 </td><td colspan=1 rowspan=1 > 464 cu in (7.6 L) inline-6 </td><td colspan=1 rowspan=1 > 1959-1974 (C160) 1959-1976 (C170/C180/C190) </td><td colspan=1 rowspan=1 > C-160D C-170D C-180D C-190D </td><td colspan=1 rowspan=1 > Rear </td><td colspan=1 rowspan=1 > Distinguished by roof-mounted external air intake (designed by Kenworth) </td></tr>
<tr> <td colspan=1 rowspan=1 > Cummins NHH </td><td colspan=1 rowspan=1 > 743 cu in (12.2 L) inline-6 743 cu in (12.2 L) turbocharged inline-6 855 cu in (14.0 L) inline-6 855 cu in (14.0 L) turbocharged inline-6 </td><td colspan=1 rowspan=1 > 1959-1973 (743) 1974-1982 (855) </td><td colspan=1 rowspan=1 > 743D 743DT 855D 855DT </td><td colspan=1 rowspan=1 > Midship </td><td colspan=1 rowspan=1 > DT=Mid-engine tandem </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > Cummins VTF555 </td><td class="highlighted"  colspan=1 rowspan=1 > 555 cu in (9.1 L) V8 </td><td colspan=1 rowspan=1 > 1975-1982 </td><td colspan=1 rowspan=1 > VTF555D VTF555DT (tandem) </td><td colspan=1 rowspan=1 > Rear </td><td colspan=1 rowspan=1 > VTF555DT is the only rear-engine tandem-axle school bus ever built </td></tr>
<tr> <td colspan=1 rowspan=1 > Detroit Diesel 6V53 </td><td colspan=1 rowspan=1 > 318 cu in (5.2 L) V6 </td><td colspan=1 rowspan=1 > 1971-1977 </td><td colspan=1 rowspan=1 > 318D </td><td colspan=1 rowspan=1 > Rear </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > Detroit Diesel 6N71 </td><td class="highlighted"  colspan=1 rowspan=1 > 426 cu in (7.0 L) inline-6 426 cu in (7.0 L) turbocharged inline-6 </td><td colspan=1 rowspan=1 > 1976-1982 </td><td colspan=1 rowspan=1 > 426D 426DT </td><td colspan=1 rowspan=1 > Midship </td><td colspan=1 rowspan=1 > 426DT=Mid-engine tandem </td></tr>
<tr> <th colspan=6 rowspan=1 > Gasoline engines </th></tr>
<tr> <td colspan=1 rowspan=1 > Ford Super Duty V8 </td><td colspan=1 rowspan=1 > 534 cu in (8.8 L) OHV V8 </td><td colspan=1 rowspan=1 > 1958-1974 </td><td colspan=1 rowspan=1 > 534D </td><td colspan=1 rowspan=1 > Rear </td><td colspan=1 rowspan=1 > Final gasoline engine used in Transit Coach </td></tr>
<tr> <td colspan=1 rowspan=1 > Hall-Scott 590 </td><td colspan=1 rowspan=1 > 590 cu in (9.7 L) SOHC inline-6 </td><td colspan=1 rowspan=1 > 1954-1959 </td><td colspan=1 rowspan=1 > 590D </td><td colspan=1 rowspan=1 > Rear </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > International Harvester RD-501 ("Red Diamond") </td><td colspan=1 rowspan=1 > 501 cu in (8.2 L) OHV inline-6 </td><td colspan=1 rowspan=1 > c.1950-1959 </td><td colspan=1 rowspan=1 > 501 </td><td colspan=1 rowspan=1 > Rear </td><td colspan=1 rowspan=1 >  </td></tr>
</table>
Question:
What powers the Gillig Transit Coach School Bus models?
Answer:
Gillig Transit Coach School Bus models 555 and 426 are powered by the Cummins VTF555 V8 and Detroit Diesel 6N71 inline-6, respectively.