Question

[cadams85]

I have a 1985 c10 has 273 gears was going to put 373 gears in it where is a good place to purchase some thanks

[SilverMachine]

I recently just did this swap a few weeks ago in my 86. These days pretty much whatever price you see on jegs or summit racing will pretty much be the standard anywhere, unless you have a pop shop around who's willing to help out. i got the All-star gears and the Auburn positraction differential...gears were around 170 i believe and the diff was around 400 or so. dont forget the gear installation kit which will run around 100 bucks.

[cadams85]

I appreciate the input I put a 355 flat top pistons in with 10 to 1 compression can't remember the cam size but have double hump heads I bought a tcI street fighter 700r them 273 suck got 20 on my truck so geared even higher

[SilverMachine]

yeah haha same! they guy who put my gears in saw the tire size and said it was more like 2.50 something that 2.73! im doing some engine work next week and got a streetfighter converter too i think. just be prepared for your speedometer to be off....i believe im running around 55 when my speedometer says 75....so it will probably be similar with yours unless you have aftermarket gauges which i dont know how that will effect it.

[Jay2Cor517]

I did this swap last year to my '86 GMC (peg-leg 2.73). After doing research, I decided on a Detroit Trutrac by EATON. But going this route meant I couldn't use the OEM axles which in the end is a good thing--they are now 30 spline Moser's. I also upgraded the diff cover to one that came with adjustable load bolts. I bought all the pieces from Summit. But you should be able find any and all the pieces from any vendor on the web. The only hiccup came when my installer didn't like one of the bearings that came in the Motive Gear installation kit. He thought it was a touch too big. He ordered a smaller size that he preferred (don't know which one or brand). Here are some links to different sites you may find handy for this project. I also included my parts list. Hope this helps, Have fun

EATON TruTrac YouTube video https://www.youtube.com/watch?v=lZmsY2YvVsc

EATON Catalog http://www.eaton.com/ecm/groups/publ.../ct_128302.pdf

Gear Ratio Calculating, SuperChevy tech article "The Numbers Game" http://www.superchevy.com/how-to/148...o-calculating/

Tire Size Comparison https://tiresize.com/comparison/

Parts List (all Summit Racing Part Numbers):
Detroit Trutrac DTL913A481
Moser Axles MSR-A3079GMTK
Motive Gear Ring and Pinion Sets MGR-GM10-373
Motive Gear Master Ring and Pinion Installation Kits MGR-R10REMKT
Timken Wheel Bearing TMK-6408
Timken Axle Seals TMK-8835S
Summit Differential Support Cover SME-8510300NL

[old Rusty C10]

I found a decent price at las vegas drivetrain parts when I was looking for parts for a mopar price was good haven't received them yet to talk quality

[abig84]

i went the cheap and easy route and just bought a rusty pos k5 blazer with no title for $400 and just swapped over the axles.

going from 273 to 373 is a big improvement

[cadams85]

Yeah that sounds like the way to go I've looked around for used rear end no luck

[cadams85]

I talked to one of my friends and he said truck is usually 30 spline he also said I would have to buy a differential probably go with positive trac he said I just couldn't put 373 gears and pinion in it anyone else no anything about this

[Rich84]

The C10's were 28 spline until 1988 they went to 30 spline.

[cadams85]

Thanks for letting me know before I buy the 30 spline then they wouldn't have worked so thanks