I am running a 265/75-16 on my crd. I run a stock tune and stock gears and I average 20-21 around town and 26 on the highway. I live in Boulder, CO. so its not like its flat. I have 130k on the ticker too, fwiw.

I am good about keeping a light foot on the throttle, but until i go to a 35" tire I'll keep the 3.73's.

What year is your CRD? I suspect that yours is an 05 as thry get better milage than the 06's which is what I have.

I do still need to swap out my u-joints to see if this helps and possibly Doc's brake fix if hit helps them run with any less drag. Hopefully he will chime in with some details.

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MUDD'S MOTORSPORT'S We do IFS lift installs ,
03 OVERLAND EDITION /Kilby-Skidrow-Mopar-4XGuard skids/ 2.5 inch TOTAL CONTROL JBA coilovers -JBA Arms/MOABS-31 FALKEN WILDPEAK AT3W / 4.10's etc, 04 Kilimanjaro Edition loaded, plus 05 KJ limited

Tom - why are you surprised?


CRD drives differently than a 3.7

totally stock the diesel puts out more torque at 1100 rpm - than the V6 flat out.

and most of the folks here have tune's that add 20% to that so why would 10% more tire slow you down?

if you look at the CRD's who did re-gear --

it's because they go off road and they want the low end back

top end the diesel loves the bigger tires.

(with the caveat - arengant has problems on the island because the speed limits are so low he can't shift into 5th while running 32's - although I think that's a small tradeoff for living in Hawaii)

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2005 CRD
stuff
Skeptic quod gratis asseritur, gratis negatur

If you calculate by the #'s for your CRD with 265/75's and 4.10's puts everything almost back into the exact same rpm and speed as stock with 235/70's and 3.73's.You loose a lot of low end even with a CRD with 265/75's and 3.73's.

Not to mention more heat buildup in the trans.

Yeah - but stock was low - it wasn't designed for the diesel - it was what they had in the pipeline for the 3.7

unless you're towing trailers - we could have run 3:54 or even 3:23's with the stock tires.

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2005 CRD
stuff
Skeptic quod gratis asseritur, gratis negatur

Agree with both atxkj and tjkj and I know from my own mistake of not regearing, I'm still 3.55 on xj with 265x75x16, and I'm sort of crawling in 4th gear on highway. A little warmer, maybe 5 degrees on tranny driving city. With stock tires I had no such issues. Thinking to regear to 3.73 when I'll rebuild the Dana 44 I have in the garage, 4.10 feels too low for the 4 speed aw4 on those tires. Regarding crd, my opinion is that its not worth regearing from 3.73 (if not going 33+ inch tires) unless you're an off road nut driving 90% on rough dirt roads...

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2005 kj CRD, samco, suncoast tc, provent, Kennedy lift pump, GDE ECO full torque, 2nd gen filter head, 245/70/16 a/t tires, mopar light bar, fumoto oil valve, OEM Skid Plates, ARB Front bumper and HD OME, tru cool LPD47391 40k GVW tranny cooler (stock cooler delete), FF Dynamics e-fan and shroud, rocker arms replaced, HDS2 190F thermostat.